Thursday

May 5, 2016
Number of results: 24,257

**physics # 1**

1. If a particle moves in a plane so that its position is described by the function x = Acosłt, and y = Asinłt, it is a.) moving with varying speed along a circle b.) moving with constant speed along a circle c.) moving with constant acceleration along a straight line d.) ...
*August 7, 2007 by gomez*

**+1 SCIENCE PHYSICS**

A FROG SAW AN INSECT ON THE GROUND AT A HORIZONTAL DISTANCE OF 30 METER FROM IT. THE FROG CAN JUMP WITH A SPEED 20 METER/SECOND IN ANY DIRECTION. IT JUMPS WITH HIS INITIAL SPEED AND LAND ON THE INSECT. A: WHAT IS THA TYPE OF MOSSION MADE BY THE FROG? B: FIND THE ANGLE THAT THE...
*August 28, 2011 by FATHIMA*

**AP physics**

A 0.278-kg volleyball approaches a player horizontally with a speed of 16.2 m/s. The player strikes the ball with her fist and causes the ball to move in the opposite direction with a speed of 22.4 m/s. (a) What impulse is delivered to the ball by the player? (Take the ...
*February 22, 2015 by alba*

**science**

A comet is in an elliptical orbit around the Sun. Its closest approach to the Sun is a distance of 4.8 x10^10 m (inside the orbit of Mercury), at which point its speed is 9.1 x10^4 m/s. Its farthest distance from the Sun is far beyond the orbit of Pluto. What is its speed when...
*July 8, 2014 by rachel*

**physics**

Two objects (m1 = 5.15 kg and m2 = 2.75 kg) are connected by a light string passing over a light, frictionless pulley as in the figure below. The 5.15-kg object is released from rest at a point h = 4.00 m above the table. (a) Determine the speed of each object when the two ...
*October 11, 2011 by dennis*

**PHYSICS**

Two objects (m1 = 4.90 kg and m2 = 2.75 kg) are connected by a light string passing over a light, frictionless pulley as in the figure below. The 4.90-kg object is released from rest at a point h = 4.00 m above the table. (a) Determine the speed of each object when the two ...
*February 25, 2013 by Lindse*

**Physics**

. (a) How high a hill can a car coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110 km/h? (b) If, in actuality, a 750-kg car with an initial speed of 110 km/h is observed to coast up a hill to a height 22.0 m above its starting ...
*June 10, 2014 by Anonymous*

**physics**

(a) How high a hill can a car coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110 km/h? (b) If, in actuality, a 750-kg car with an initial speed of 110 km/h is observed to coast up a hill to a height 22.0 m above its starting point...
*June 10, 2014 by Anonymous*

**Physics**

(a) How high a hill can a car coast up (engine disengaged) if work done by friction is negligible and its initial speed is 110 km/h? (b) If, in actuality, a 750-kg car with an initial speed of 110 km/h is observed to coast up a hill to a height 22.0 m above its starting point...
*June 10, 2014 by Anonymous*

**ap physics**

can you check my answers? 2.is more work required to bring a fully loaded truck up to a given speed, than the same truck lightly loaded? defend your answer? -more work is required to bring a fully loaded truck up to a given speed because it is doing more work since it is fully...
*October 16, 2007 by Elisabeth*

**Maths/Science**

Please could someone remind me how to calculate mean speed? I have to work out the mean speed of lava flow that travelled 13.5km over 21 days. I don't expect the answer, but some help on how to obtain it would be heplful! Thank you. All you can do is average speed: Average ...
*May 7, 2007 by Bean*

**physics SHM**

A particle is moving with SHM of period 16s and amplitude 10m. Find the speed of teh particle when it is 6.0m from its equilibrium position. First I found the value of w: w= 2 pi/ T = 2 pie/ 16 =0.393 s^-1 Then I used: v= +/- w root a^2 - x^2 = +/- 0.393 root 10^2 - 6^2 = 3.14...
*December 28, 2007 by Claire*

**college physics 1**

Reviewing Interactive Solution 5.46 will help in solving this problem. A stone is tied to a string (length = 1.29 m) and whirled in a circle at the same constant speed in two different ways. First, the circle is horizontal and the string is nearly parallel to the ground. Next...
*March 5, 2014 by anonymous*

**physics**

An enemy plane is flying horizontally at an altitude of 2.0km with a speed of 340m/s.An army man with anti-craft gun on the ground sight the enemy with a muzzle speed at 60m/s .when the enemy plane is directly overhead.find a)at what angle from the verticals should the gun be ...
*January 16, 2016 by henro*

**Physics... Please Help**

An arrow is fired with a speed of 20.0 m/s at a block of Styrofoam resting on a smooth surface. The arrow penetrates a certain distance into the block before coming to rest relative to it. During this process the arrow's deceleration has a magnitude of 1300 m/s2 and the block'...
*October 14, 2009 by Robert C*

**Physics**

At the airport they have people movers (horizontal escalators). Your friend decides to use the people mover and since you've been sitting decide to walk along side. You would like to continue your conversation and thus need to continue moving at the same speed. Assuming your ...
*September 16, 2013 by Kelsey*

**Physics**

A trapeze artist, starting from rest, swings downward on the bar, lets go at the bottom of the swing, and falls freely to the net. An assistant, standing on the same platform as the trapeze artist, jumps from rest straight downward. Friction and air resistance are negligible...
*May 8, 2007 by Papito*

**Physics**

A 15 kg model airplane flies horizontally at point A that is 20 m about point B. It has a speed of 19.993 m/s at point A. It then flies horizontally at point B. If the loss of potential energy is reflected as an increase in kinetic energy, what is the speed of the model ...
*November 17, 2011 by Brooke*

**Physics**

A particle rotates in a circle with centripetal acceleration a = 8.8 m/s2 . What is a if the radius is doubled without changing the particle's speed? What is a if the speed is doubled without changing the circle's radius?
*October 12, 2015 by Shiv*

**physics**

a 1.5-kg object moves up the y-axis at a constant speed. When it reaches the origin,the forces F1 =5.0 N at 37 deg above the the + x-axis, F2 = 2.5 N in the +x-direction, F3 = 3.5 N at 45 deg below the -x-axis, and F4 = 1.5 N in the -y direction are applied to it(a) Will the ...
*January 17, 2008 by melissa*

**Physics**

Now your bicycle wheel is rotating with an angular speed of 43.8 rad/s. The wheel has a mass of 4.9 kg and a radius of 48.6 cm. Treat the wheel as a solid thin disc. (a) Calculate the rotational kinetic energy of the wheel in J. (b) Calculate the angular speed the wheel must ...
*April 22, 2016 by Jannia*

**Physics**

A bullet with a mass m = 4:83 g and initial speed of 330 m/s passes through a wheel which is initially at rest as in the The wheel is a solid disk with mass M = 2.29 kg and radius R = 1.:6 cm. The wheel rotates freely about an axis through its center and out of the plane shown...
*December 25, 2011 by Lindsay*

**Physics **

A 91 kg man stands on a spring scale in an elevator. Starting from rest, the eleva- tor ascends, attaining its maximum speed of 1.7 m/s in 1.07 s. It travels with this constant speed for the next 5 s, undergoes a uniform negative acceleration for 1.67 s, and comes to rest. ...
*January 11, 2016 by Mariah *

**calculus**

2. A bullet is fired from the ground at an angle of 45o above the horizontal. What initial speed vo must the bullet have in order to hit a point 550 ft high on a tower located 600 ft away (ignoring air resistance)? 3. The Giant Ferris Wheel in Vienna has radius R = 30 m (...
*April 14, 2012 by nady*

**Physics**

In attempting to pass the puck to a teammate, a hockey player gives it an initial speed of 2.0m/s, but because of the kinetic friction between the puck and the ice, the puck travels only half the distance between the players before coming to rest. Assuming that the ice's ...
*December 4, 2009 by John*

**Precalculus**

An observer 2 km from the launching pad observes a vertically ascending missile at an angle of elevation of 21 degrees. 5 seconds later the nagle has increased to 35 degrees. What was its average speed during this interval? If it keeps going vertically at the same average ...
*December 1, 2010 by Harchit*

**physics**

Three objects lie in the x, y plane. Each rotates about the z axis with an angular speed of 4.44 rad/s. The mass m of each object and its perpendicular distance r from the z axis are as follows: (1) m1 = 6.00 kg and r1 = 1.00 m, (2) m2 = 4.50 kg and r2 = 7.10 m, (3) m3 = 3.60 ...
*April 22, 2014 by Anonymous*

**physics**

The sun has a mass of 1.99 × 1030 kg and is moving in a circular orbit about the center of our galaxy, the Milky Way. The radius of the orbit is 2.3 × 104 light-years (1 light-year = 9.5 × 1015 m), and the angular speed of the sun is 1.1 × 10-15 rad/s. a) Determine the ...
*March 9, 2015 by Jennifer*

**physics(kinematics)**

A police officer in a patrol car parked in a 70 Km/h speed zone observes a passing automobile might be intoxicated,the officer starts his car,accelerates uniformly to 90 Km/h in 8s ,and maintaining a constant velocity of 90 Km/h,overtakes the motorist 42s after the automobile ...
*July 31, 2015 by benjamin*

**Physics**

The Giant Swing ride consists of a vertical shaft with a number of horizontal arms attached at the top as shown. A rigid cable 5.0 m long connects a seat to the arm at a point 2.0 m from the center shaft. When the ride reaches its full speed, the angle made by the arm is 35....
*February 24, 2013 by Meder*

**Physics**

A plane, diving with constant speed at an angle of 52.0° with the vertical, releases a projectile at an altitude of 790 m. The projectile hits the ground 6.00 s after release. (Assume a coordinate system in which the airplane is moving in the positive horizontal direction, and...
*September 26, 2013 by Matt*

**Physics**

A plane, diving with constant speed at an angle of 52.0° with the vertical, releases a projectile at an altitude of 790 m. The projectile hits the ground 6.00 s after release. (Assume a coordinate system in which the airplane is moving in the positive horizontal direction, and...
*September 26, 2013 by URGENT PLS HELP*

**Chemistry problem**

The formula for the Maxwell-Boltzmann distribution is given below,where y is proportional to the fraction of particles of molecular mass m at temperature T traveling at speed u. The expression frac(u1,u2) gives the fraction of particles between speeds of u1 and u2. Determine ...
*April 25, 2016 by windal*

**math**

Jim and Joe were running together. Jim's average speed was 400 meters per minute.Jim started running four minutes before Joe. ten minutes after Joe started, he caught up with Jim. What was Joe's average speed?
*November 29, 2011 by iris*

**math**

Please explain how to solve: The wavelength of a radio wave is defined as speed divided by frequency. An FM radio station has a frequency of 9 x 10(power of 7) waves per second. The speed of the waves is about 3 x 10 (power of 8) meters per second. What is the wavelength of ...
*January 5, 2012 by Jane*

**Physics**

A fire helicopter carries a 555 kg empty water bucket at the end of a cable 20.9 m long. As the aircraft flies back from a fire at a constant speed of 38.4 m/s, the cable makes an angle of 38.3° with respect to the vertical. A) After filling the bucket with sea water, the ...
*September 27, 2011 by Bella*

**Physics**

A fire helicopter carries a 555 kg empty water bucket at the end of a cable 20.9 m long. As the aircraft flies back from a fire at a constant speed of 38.4 m/s, the cable makes an angle of 38.3° with respect to the vertical. A) After filling the bucket with sea water, the ...
*September 28, 2011 by Bella*

**Physics**

A fire helicopter carries a 555 kg empty water bucket at the end of a cable 20.9 m long. As the aircraft flies back from a fire at a constant speed of 38.4 m/s, the cable makes an angle of 38.3° with respect to the vertical. A) After filling the bucket with sea water, the ...
*September 28, 2011 by pete*

**Physics please answer the a) for me :(**

Ill do the rest. A ball was thrown up at 25.0 m/s. It was released when it was 2.0 m above the ground. a) For how long did the ball rise? b) at the top of its trajectory, how far above the ground was it? c) what was the ball's speed, direction and height 2.0 s after release? d...
*November 9, 2010 by Michael*

**Physics**

A man of mass 75.5 kg walks down the aisle of an airplane at a speed of 1.50 m/s in the forward direction while the plane moves at a speed of 305 m/s relative to the earth. (a) Find the man's kinetic energy relative to the plane. (b) Find the man's kinetic energy relative to ...
*October 10, 2011 by Kellie *

**NCSU**

A man of mass 83.5 kg walks down the aisle of an airplane at a speed of 1.60 m/s in the forward direction while the plane moves at a speed of 295 m/s relative to the earth. (a) Find the man's kinetic energy relative to the plane. (b) Find the man's kinetic energy relative to ...
*March 24, 2012 by Amber*

**physics**

A man of mass 78.5 kg walks down the aisle of an airplane at a speed of 1.40 m/s in the forward direction while the plane moves at a speed of 320 m/s relative to the earth. (a) Find the man's kinetic energy relative to the plane. (b) Find the man's kinetic energy relative to ...
*April 4, 2013 by Help*

**Physics 1**

A golf ball of mass 125 g hits a billiards ball of mass 172.5 g that is initially at rest. After the collision, the golf ball moves to the right at a speed of 10 cm/s. The billiards ball moves to the left with a speed of 58 cm/s. (a) What was the velocity of the golf ball ...
*March 8, 2016 by David*

**pHYSICS**

A BALL IS THROWN STRIAGHT UPWARD AND RETURMS TO THE THROWER'S HAND AFTER 3 SECONDS IN THE AIR. A SECOND BALL IS THROWN AT AN ANGLE OF 30 DEGREES WITH THE HORIZONTAL. AT WHAT SPEED MUST THE 2ND BALL BE THROWN SO THAT IT REACHES THE SAME HIEGHT AS THE ONE THORWN VERTICALLY? I ...
*November 1, 2006 by Jill Hefner*

**Physics**

You are practicing throwing darts in your dorm. You stand 3.21 m from the wall on which the board hangs. The dart leaves your hand with a horizontal velocity at a point 1.94 m above the ground. The dart strikes the board at a point 1.73 m from the ground. a) Calculate the time...
*January 27, 2015 by Sally*

**College algebra**

It took Eric 8 hours to drive to a job interview. On the way home, he was able to increase his average speed by 18mph and make the return drive in only 5 hours. Find his average speed on the return drive. Rate x time =distance Original drive- x. ____ _____ Return drive- ____ ...
*January 24, 2016 by Tyler*

**Physics**

A cyclist approaches the bottom of a gradual hill at a speed of 20 m/s. The hill is 4.4 m high, and the cyclist estimates that she is going fast enough to coast up and over it without peddling. Ignoring air resistance and friction, find the speed at which the cyclist crests ...
*February 25, 2008 by Zach*

**Pre-Algebra**

Question is: What is the algebraic equation to determine when they will meet? For the following information, I understand 5(x+y) = 3000 for 1st plane & 10(x-y) = 3000 for 2nd plane. When an airplane flies with a given wind, it can travel 3000 km in 5hrs. When the same airplane...
*November 13, 2011 by Carol*

**Pre-Algebra**

Question is: What is the algebraic equation to determine when they will meet? For the following information, I understand 5(x+y) = 3000 for 1st plane & 10(x-y) = 3000 for 2nd plane. When an airplane flies with a given wind, it can travel 3000 km in 5hrs. When the same airplane...
*November 13, 2011 by Carol*

**mit physics**

A spherical non-rotating planet (with no atmosphere) has mass m 1= 6 ×10 24 kg and radius r 1= 9000 km. A projectile of mass m 2≪ m 1 is fired from the surface of the planet at a point A with a speed v A at an angle α=30 ∘ with respect to the radial direction...
*December 6, 2013 by juanpro*

**Physics**

A Cessna 150 aircraft has a lift-oﬀ speed of approximately 125 km/h. What minimum constant acceleration does this require if the aircraft is to be airborne after a take-oﬀ run of 172 m? Answer in units of m/s2 What is the corresponding take-oﬀ time? Answer...
*October 13, 2011 by Asdfghjkl*

**physics**

A box of unknown mass is sliding with an initial speed vi = 5.60 m/s across a horizontal frictionless warehouse floor when it encounters a rough section of flooring d = 3.40 m long. The coefficient of kinetic friction between the rough section of flooring and the box is 0.100...
*July 8, 2013 by Amy*

**Physics**

Blood flow rates in the umbilical cord can be found by measuring the Doppler shift of the ultrasound signal reflected by the red blood cells. If the source emits a frequency f, what is the measured reflected frequency fR? Assume that all of the red blood cells move directly ...
*January 13, 2016 by Becky*

**physics**

(a) What is the tangential acceleration of a bug on the rim of a 6.0 in. diameter disk if the disk moves from rest to an angular speed of 79 rev/min in 5.0 s? m/s2 (b) When the disk is at its final speed, what is the tangential velocity of the bug? m/s (c) One second after the...
*March 27, 2010 by Kelsey*

**Physics**

Let's consider some of the things that affect the velocity of a standing wave on a string: decide whether each of the following statements are T-True, or F-False. (If the first is T and the rest are F, enter TFFFF) A) The velocity of the wave traveling on a string is higher if...
*March 31, 2011 by College student in need of help*

**Physics**

A baseball with a mass of 150 g is thrown horizontally with a speed of 39.5 m/s (88 mi/h) at a bat. The ball is in contact with the bat for 1.15 ms and then travels straight back at a speed of 45.0 m/s (101 mi/h). Determine the average force exerted on the ball by the bat. ...
*March 2, 2014 by Elaine*

**Physics help **

A 31.0 kg child on a swing reaches a maximum height of 1.92 m above their rest position. Assuming no loss of energy: a) At what point during the swing will she attain their maximum speed? b) What will be her maximum speed through the subsequent swing? c) Assuming this maximum ...
*January 11, 2016 by Help me in Physics*

**physics**

Eris, the largest dwarf planet known in the Solar System, has a radius R = 1200 km and an acceleration due to gravity on its surface of magnitude g = 0.77 m/s2. (a) Use these numbers to calculate the escape speed from the surface of Eris. 1360 m/s correct answer. (b) If an ...
*October 30, 2011 by mymi*

**Physics**

A hockey player is standing on his skates on a frozen pond when an opposing player, moving with a uniform speed of 2.0 m/s, skates by with the puck. After 1.00 s, the first player makes up his mind to chase his opponent. If he accelerates uniformly at 0.20 m/s2, determine each...
*September 13, 2015 by Tina*

**Vibration and Wave Fundamentals**

Vibration and Wave Fundamentals 1. A machine gun fires 10 rounds per second. The speed of the bullets is 300 m/s. (A.) What is the distance in the air between the flying bullets? ____ ANSWER=30 (B.)What happens to the distance between the bullets if the rate of fire is ...
*January 24, 2010 by Sam*

**Physics **

An automobile with a mass of 1450 kg is parked on a moving flatbed railcar; the flatbed is 1.50 m above the ground. The railcar has a mass of 38500 kg and is moving to the right at a constant speed of 8.70 m/s on a frictionless rail. The automobile them accelerates to the left...
*January 19, 2016 by Khalid*

**Physics**

***EXTRA CREDIT*** An arrow is fired with a speed of 20.0 m/s at a block of Styrofoam resting on a smooth surface. The arrow penetrates a certain distance into the block before coming to rest relative to it. During this process the arrow's deceleration has a magnitude of 1300 ...
*October 13, 2009 by Robert C*

**physics**

Two cars leave the same point at the same time, each travelling at the same constant speed of 89.0 km/h and each having the same mass. However, the first car drives directly east, while the second car heads directly south. At what speed (the magnitude of the velocity) is the ...
*November 7, 2014 by Anonymous*

**physics**

Two cars leave the same point at the same time, each travelling at the same constant speed of 89.0 km/h and each having the same mass. However, the first car drives directly east, while the second car heads directly south. At what speed (the magnitude of the velocity) is the ...
*November 7, 2014 by Anonymous*

**physics**

Two cars leave the same point at the same time, each travelling at the same constant speed of 89.0 km/h and each having the same mass. However, the first car drives directly east, while the second car heads directly south. At what speed (the magnitude of the velocity) is the ...
*November 7, 2014 by Anonymous*

**physics**

Two cars leave the same point at the same time, each travelling at the same constant speed of 89.0 km/h and each having the same mass. However, the first car drives directly east, while the second car heads directly south. At what speed (the magnitude of the velocity) is the ...
*November 7, 2014 by Anonymous*

**physics**

On a drive from your home to town, you wish to average 52 mph. The distance from your home to town is 106 miles. However, at 53 miles (half way), you ﬁnd you have averaged only 39 mph. What average speed must you maintain in the remaining distance in order to have an ...
*August 9, 2012 by amanda and leah*

**Physics**

On a drive from your home to town, you wish to average 44 mph. The distance from your home to town is 106 miles. However, at 53 miles (half way), you find you have averaged only 33 mph. What average speed must you maintain in the remaining distance in order to have an overall ...
*August 20, 2015 by Joe*

**Physics **

On a drive from your home to town, you wish to average 52 mph. The distance from your home to town is 108 miles. However, at 54 miles (half way), you find you have averaged only 39 mph. What average speed must you maintain in the remaining distance in order to have an overall ...
*September 9, 2015 by Karen *

**math**

A race car driver starts along a 50-mile race course traveling at an average speed of 90 mph. Fifteen minutes later a second driver starts along the same course at an average speed of 120 mph. Will the second car overtake the first car before the drivers reach the end of the ...
*July 28, 2011 by Anonymous*

**Physics**

A long-range jet liner flies (almost exactly) level at constant speed, subject to the forces of drag fD=(1/2)CDrhoSv^2, thrust Ft, and weight Mg. Given the plane's wing area, lift and drag coefficients, speed and takeoff mass, calculate the engine power required for level ...
*May 10, 2011 by Ferdinand*

**Physics**

A long-range jet liner flies (almost exactly) level at constant speed, subject to the forces of drag fD=(1/2)CDrhoSv^2, thrust Ft, and weight Mg. Given the plane's wing area, lift and drag coefficients, speed and takeoff mass, calculate the engine power required for level ...
*May 10, 2011 by Ferdinand*

**Math**

Flying into the wind, a plane takes 8h to travel 5432 km from Paris to Montreal.The same plane flying with the wind from Montreal to Paris takes only 7 h. Find the speed of the plane and the speed of the wind.
*January 22, 2009 by gagan*

**physics**

An amusement park ride consists of a car moving in a vertical circle on the end of a rigid boom of negligible mass. The combined weight of the car and riders is 5.1 kN, and the circles radius is 10 m. At the top of the circle, what are the (a) magnitude FB and (b) direction (...
*March 2, 2010 by beav*

**physics**

A steel ball of mass 0.300 kg is fastened to a cord that is 70.0 cm long and fixed at the far end. The ball is then released when the cord is horizontal. At the bottom of its path, the ball strikes a 2.50 kg steel block initially at rest on a frictionless surface. The ...
*March 28, 2011 by Taylor*

**physics**

A 68.0 kg person throws a 0.0450 kg snowball forward with a ground speed of 27.0 m/s. A second person, with a mass of 58.0 kg, catches the snowball. Both people are on skates. The first person is initially moving forward with a speed of 2.50 m/s, and the second person is ...
*March 28, 2011 by Alexandria*

**physics **

A 69.0 kg person throws a 0.0410 kg snowball forward with a ground speed of 35.0 m/s. A second person, with a mass of 60.0 kg, catches the snowball. Both people are on skates. The first person is initially moving forward with a speed of 2.00 m/s, and the second person is ...
*June 2, 2011 by sam*

**physics **

A 69.0 kg person throws a 0.0410 kg snowball forward with a ground speed of 35.0 m/s. A second person, with a mass of 60.0 kg, catches the snowball. Both people are on skates. The first person is initially moving forward with a speed of 2.00 m/s, and the second person is ...
*June 2, 2011 by sam*

**physics**

A 66.0-kg person throws a 0.0450-kg snowball forward with a ground speed of 35.0 m/s. A second person, with a mass of 57.0 kg, catches the snowball. Both people are on skates. The first person is initially moving forward with a speed of 2.40 m/s, and the second person is ...
*October 16, 2011 by Anonymous*

**AP physics B**

A billiards cue ball of mass 0.380 kg has a perfectly elastic head-on collision with a standard pool ball. The second pool ball which started at rest travels with a speed which is half the original speed of the cue ball. (a) Calculate the mass of the pool ball. kg (b) ...
*November 2, 2012 by Need help fast*

**Physics **

Consider a wet roadway banked as in the following figure, where there is a coefficient of static friction of 0.30 and a coefficient of kinetic friction of 0.25 between the tires and the roadway. The radius of the curve is R = 50 m. (a) If the banking angle is 25o, what is the ...
*September 23, 2014 by HelpMaths*

**Physics**

A bullet of mass 5.15 g is fired horizontally into a 2.74 kg wooden block at rest on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.185. The bullet comes to rest in the block, which moves 1.84 m. (a) What is the speed of the block ...
*November 21, 2010 by confused*

**Math**

A student is in a 20 week calc class. The function f(t)=50-50e^0.2t f(t) measures the students problem speed in t weeks -how many problems per hour can a student solve at the beginning of the course - how many problems per hour can a student solve halfway through the course -...
*July 20, 2012 by Marshall*

**Physics **

A pendulum consists of a swinging mass hanging from a massless string. The hanging mass is 2.0 kg and the string is 400.0 cm long. If the mass has a speed of 8.0 m/s when it passes the lowest point of its swing, a) what is the speed when the string makes an angle of 60.0o with...
*May 30, 2014 by Tom*

**Physics **

A roller-coaster car speeds down a hill past point A where R1 = 9.8 m and then rolls up a hill past point B where R2 = 15.8 m (R1 and R2 represent the radiuses/ radii) The car has a speed of 18.6 m/s at point A. if the track exerts a normal force on the car of 2.16 104 N at ...
*December 20, 2010 by Tori*

**Physics**

A roller-coaster car speeds down a hill past point A where R1 = 8.2 m and then rolls up a hill past point B where R2 = 15.4 m, as shown below. (a) The car has a speed of 21.0 m/s at point A. if the track exerts a normal force on the car of 2.30 ✕ 104 N at this point, ...
*December 16, 2014 by Anonymous*

**Physics**

A roller-coaster car speeds down a hill past point A where R1 = 10.4 m and then rolls up a hill past point B where R2 = 15.6 m, as shown below. R1 and 2 are radii (a) The car has a speed of 21.0 m/s at point A. if the track exerts a normal force on the car of 2.05 multiplied ...
*November 1, 2012 by Angela*

**Math URGENT!!**

The speed of a runner increased steadily during the first three seconds of a race. Her speed at half-second intervals is given in the table. Find a lower estimate for the distance that she traveled during these three seconds. t(s) 0 0.5 1.0 1.5 2.0 2.5 3.0 v(ft/s) 0 3 6.6 9.9 ...
*April 14, 2007 by Christina*

**Physics **

Two hockey pucks approach each other as shown in the figure below. Puck 1 has an initial speed of 22 m/s, and puck 2 has an initial speed of 14 m/s. They collide and stick together. Find the components along x and y of the initial velocities of both particles. v1xi = 19.1 m/s ...
*November 14, 2010 by J Velji*

**physics**

An entertainer juggles balls while doing other activities. In one act, she throws a ball vertically upward, and while it is in the air, she runs to and from a table 5.20m away at a constant speed of 2.40m/s, returning just in time to catch the falling ball. A) With what ...
*July 8, 2011 by izzy*

**Physics/Calculus**

An automobile with a mass of 1316 kg is parked on a moving flatbed railcar; the flatbed is 1.5 m above the ground. The railcar has a mass of 40,810 kg and is moving to the right at a constant speed v = 8.8 m/s on a frictionless rail. The automobile then accelerates to the left...
*October 7, 2010 by Sarah*

**physics**

(a) Calculate the mass flow rate (in grams per second) of blood (ρ = 1.0 g/cm3) in an aorta with a cross-sectional area of 2.0 cm2 if the flow speed is 33 cm/s. Answer is in g/s (b) Assume that the aorta branches to form a large number of capillaries with a combined cross...
*October 27, 2011 by caitlin*

**Physics**

(a) A small mail bag is released from a helicopter that is descending steadily at 2.13 m/s. After 4.38 s, what is the speed of the mail- bag? The acceleration of gravity is 9.8 m/s2 . (b) After the mailbag is dropped, the helicopter continues descending for 1 s but then stops...
*October 26, 2014 by Nina*

**mechanics**

A roller of radius 400mm rolls without slip between two parallel plates moving in opposite direction with speed,upper plate=7m/s(”ś),lower plate=4m/s(”ū). Determine (a) the location of instantaneous centre with respect to lower plate,(b)the location of instantaneous centre ...
*December 9, 2014 by sneha*

**physics**

The balance wheel of a watch oscillates with angular amplitude 1.7π rad and period 0.64 s. Find (a) the maximum angular speed of the wheel, (b) the angular speed of the wheel at displacement 1.7π/2 rad, and (c) the magnitude of the angular acceleration at ...
*January 9, 2011 by kylie*

**Algebra**

A plane traveled 580 miles to Anakara and back. The trip there was with the wind. It took 5 hours. The trip back was into the wind. The trip back took 10 hours. Find the speed of the plane in still air and the speed of the wind.
*July 18, 2012 by Taurus*

**physics**

A skier leaves the starting gate at the top of a ski ramp with an initial speed of 4.00 m/s (Figure 6-41). The starting position is 120 m higher than the end of the ramp, which is 3.00 m above the snow. Find the final speed of the skier if he lands 145 m down the 20.0° slope. ...
*October 31, 2014 by nic*

**physics**

A skier leaves the starting gate at the top of a ski ramp with an initial speed of 4.00 m/s (Figure 6-41). The starting position is 120 m higher than the end of the ramp, which is 3.00 m above the snow. Find the final speed of the skier if he lands 145 m down the 20.0° slope. ...
*October 31, 2014 by chris*

**Algebra**

Ben traveled by car at an average speed of 29 miles per hour. Then, he traveled by motorcycle at an average speed of 53 miles per hour. In total, he traveled 333 miles for 9 hours. How many minutes did Ben travel by motorcycle? (Round to the nearest minute.)
*August 13, 2012 by Charlotte*

**physics**

You see some management students getting drunk at 1 PM in the quad. (Yes, this is an early wake up call for them.) You decide to tie a 2.00 daN water balloon on the end of a 1.00 m long light rope and start swinging it horizontally. The rope from your hand to the water balloon...
*March 22, 2016 by BOB*