Wednesday

August 31, 2016
Number of results: 24,670

**Physics**

Two children are playing on two trampolines. The first child can jump one and a half times higher than the second child. The initial speed of the second child is 5 m/s. What is the maximum height of the second child? What is the initial speed of the first child? How long was ...
*October 12, 2014 by Jim*

**Physics URGENT!!!**

A 75.0 kg fullback running east with a speed of 6.00 m/s is tackled by a 82.0 kg opponent running north with a speed of 5.00 m/s. (a) Calculate the velocity of the players immediately after the tackle. (b)Calculate the direction of the players immediately after the tackle.(c)...
*October 17, 2012 by Megan*

**Physics**

4. A football player passes the ball. The ball leaves his hand and is caught 1.7 seconds later by a receiver 30 meters away. (You may assume the ball was caught at the same height from which it was thrown.) a) What is the vertical component of the velocity of the ball just ...
*October 5, 2012 by Anonymous*

**physics**

A pelican ﬂying along a horizontal path drops a ﬁsh from a height of 6.0 m. The ﬁsh travels 7.7 m horizontally before it hits the water below. What was the pelican’s initial speed? The acceleration of gravity is 9.81 m/s 2. If the pelican was traveling at ...
*October 9, 2012 by David*

**Math**

I don't understand this question, could someone solve/walk me through this? One afternoon in Fort Simpson, Northwest Territories, the air temperature was −10ºC and the wind speed was 25 km/h. The air temperature dropped by 5ºC in the evening, but the wind chill did not ...
*February 5, 2014 by Dennis*

**physics**

As it passes over Grand Bahama Island, the eye of a hurricane is moving in a direction 60.7° north of west with a speed of 37.4km/hr. Two hours later, the course of the hurricane suddenly shifts due north and its speed slows to 21.0km/hr. How far from Grand Bahama is the eye 5...
*September 22, 2014 by afia*

**Physics**

A Bugatti Veyron 16.4 can accelerate from 0 to 60 mi/h in 2.4 s. The Saleen S7 Twin Turbo goes "from 0 to 60" in 2.8 s. Determine the distance that the Bugatti Veyron would travel in the time it takes to reach 75 km/h, the speed limit on many Canadian roads. Compare your ...
*August 29, 2015 by Alyssa*

**Precalculus**

The quarterback of a football team releases a pass at a height of 7 feet above the playing field, and the football is caught at a height of 4 feet, 30 yards directly downfield. The pass is released at an angle of 35 degrees with the horizontal. The parametric equations for the...
*April 21, 2014 by Brittany*

**physics**

Suppose a fixed cannon is to fire a projectile at an enemy tank, which is moving toward the cannon at a speed of 15 mph. If the cannon is to fire at the moment the tank is 3 miles from the cannon and the muzzle speed of the cannon is 1100 mph, what is the correct equation to ...
*April 6, 2010 by drew*

**Physics**

A variable-length air column is placed just below a vibrating wire that is fixed at the both ends. The length of air column open at one end is gradually increased from zero until the first position of resonance is observed at 20 cm. The wire is 115.4 cm long and is vibrating ...
*October 1, 2012 by AJ*

**Physics**

A variable-length air column is placed just below a vibrating wire that is fixed at the both ends. The length of air column open at one end is gradually increased from zero until the first position of resonance is observed at 20 cm. The wire is 115.4 cm long and is vibrating ...
*October 5, 2012 by AJ*

**Physics**

In the figure below, an electron is moving rightward between two parallel charged plates separated by distance d = 2.40 mm. The particle is speeding up from an initial speed of 3620 km/s at the left plate. ｜ ｜ &#...
*January 31, 2013 by ann*

**Physics**

Given: G = 6.67259 × 10−11 Nm2/kg2 . A 602 kg geosynchronous satellite or- bits a planet similar to Earth at a radius 1.98 × 105 km from the planet’s center. Its angular speed at this radius is the same as the rotational speed of the Earth, and so they ap- pear ...
*February 7, 2012 by Holly *

**Physics**

Two blocks, each with a mass = 0.168 kg, can slide without friction on a horizontal surface. Initially, block 1 is in motion with a speed = 1.28 m/s; block 2 is at rest. When block 1 collides with block 2, a spring bumper on block 1 is compressed. Maximum compression of the ...
*March 5, 2012 by Lilly *

**trigonometry**

The sprockets and chain of a bicycle are shown in the figure. The pedal sprocket has a radius of 4 in., the wheel sprocket a radius of 2 in., and the wheel a radius of 13 in. The cyclist pedals at 45 rpm. (a) Find the angular speed of the wheel sprocket. rad/min (b) Find the ...
*November 29, 2012 by monic*

**physics**

Two blocks, each with a mass m = 0.400 kg, can slide without friction on a horizontal surface. Initially, block 1 is in motion with a speed $v$ = 1.20 m/s; block 2 is at rest. When block 1 collides with block 2, a spring bumper on block 1 is compressed. Maximum compression of ...
*March 5, 2014 by Ted*

**physics**

A uniform solid cylinder of radius R and a thin uniform spherical shell of radius R both roll without slipping. If both objects have the same mass and the same kinetic energy, what is the ratio of the linear speed of the cylinder to the linear speed of the spherical shell?
*December 5, 2011 by saud*

**physics**

Water is circulating through a closed system of pipes in a two- floor apartment. On the first floor, the water has a gauge pressure of 3.4*10^5 Pa and a speed of 2.1 m/s. However, on the second floor, which is 4.0 m higher, the speed of the water is 3.7 m/s. The speeds are ...
*April 17, 2012 by Fluids, Pressure, Bernoulliâ€™s Equation*

**Projectile**

An enemy plane is flying horizontall at a distance 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 Skykid*

**PHYSICS**

A 60.8-kg skateboarder starts out with a speed of 1.84 m/s. He does 90.8 J of work on himself by pushing with his feet against the ground. In addition, friction does -278 J of work on him. In both cases, the forces doing the work are non-conservative. The final speed of the ...
*April 22, 2015 by KS*

**Physics**

The siren of a police car produces a sound of frequency 420Hz.A man sitting next to the road notices that the pitch of the sound changes as the car moves towards and then away from him.1- WRITE DOWN THE NAME OF THE PHENOMENON. 2-ASSUME THAT THE SPEED OF THE SOUND IN AIR IS ...
*October 12, 2010 by Lydia*

**physics**

A toboggan is sliding down a snowy slope. The table shows the speed of the toboggan at various times during its trip. (a) Make a graph of the speed as a function of time. (b) Judging by the graph, is it plausible that the toboggan’s acceleration is constant? If so, what is the...
*September 6, 2011 by John*

**Phsyics**

A projectile is fired with an initial speed of 61.3m/s at an angle of 44.2∘ above the horizontal on a long flat firing range. (a) Determine the maximum height reached by the projectile. (b) Determine the total time in the air. (c) Determine the total horizontal distance ...
*September 15, 2013 by Tucker*

**PHYSICS ENERGY CONSERVATION!!**

The car shown in the figure has a mass of 395 kg when it passes through point A with a speed of 17.7 m/s, being the height of A 7.2 m above the ground (y = 0). In the instant that passes through C its speed is diminished to 7.6 m/s. Assuming that the path has no friction (a) ...
*April 10, 2016 by Malcolm*

**algebra**

9. 9/5w + 8/w ** Cannot be simplified. Am I correct?? 14. The number of instrctions N performed per second by a computer varies directly as the speed S of the computer's internal processor. A processor with a speed of 20 megahertz an perform 1,800,000 instructions per second. ...
*September 26, 2013 by Help*

**Algbra**

It’s the end of the semester, and sisters Sarah and Chelsea are eager to head home for the summer. It’s a long drive, and Sarah’s old car can manage an average speed of only 55 miles per hour, so she leaves early in the morning. An hour later, Chelsea follows her at an average...
*April 24, 2015 by Brian*

**Algebra**

It’s the end of the semester, and sisters Sarah and Chelsea are eager to head home for the summer. It’s a long drive, and Sarah’s old car can manage an average speed of only 55 miles per hour, so she leaves early in the morning. An hour later, Chelsea follows her at an average...
*April 24, 2015 by Brian*

**Physics**

A power boat of mass 495 kg is cruising at a constant speed of 8.9 m/s. The propeller provides a drive force of 780 N. The driver of the boat shuts off the engine, and the boat coasts to a halt. Assume-contrary to fact-that the resistive force due to the water is constant, ...
*February 25, 2008 by John*

**Physics**

A power boat of mass 460 kg is cruising at a constant speed of 8.9 m/s. The propeller provides a drive force of 765 N. The driver of the boat shuts off the engine, and the boat coasts to a halt. Assume-contrary to fact-that the resistive force due to the water is constant, ...
*February 25, 2008 by Peter*

**physics**

A power boat of mass 465 kg is cruising at a constant speed of 8.9 m/s. The propeller provides a drive force of 765 N. The driver of the boat shuts off the engine, and the boat coasts to a halt. Assume-contrary to fact-that the resistive force due to the water is constant, ...
*October 23, 2010 by Xavier*

**Physics**

The A string of a violin is 31 cm long between fixed points with a fundamental frequency of 440 Hz and a mass per unit length of 5.8×10^−4 kg/m. What are the wave speed in the string? What are the tension in the string? What is the length of the tube of a simple wind ...
*December 7, 2010 by Jake*

**Physics**

question 1 ..A 5 kg rock is thrown vertically upward at 12 m/s. How high did the rock rise? question 2 The driver of a truck traveling at 126 km/h on a highway sees a sign which indicated that 800 m after the sign the maximum speed will be 90 km/h . When the truck passes the ...
*November 21, 2015 by Axe*

**Algebra**

Two trains, one going from Boston to New York and the other going from New York to Boston, started their trips at exactly same time. Speed of the first train was 10 miles per hour less than twice the speed of the second train. How far from Boston station have they met, if the ...
*February 27, 2016 by Anish Panda*

**Algebra**

Two trains, one going from Boston to New York and the other going from New York to Boston, started their trips at exactly same time. Speed of the first train was 10 miles per hour less than twice the speed of the second train. How far from Boston station have they met, if the ...
*March 1, 2016 by Emily*

**physics**

Heather and Jerry are standing on a bridge 53m above a river. Heather throws a rock straight down with a speed of 12m/s . Jerry, at exactly the same instant of time, throws a rock straight up with the same speed. Ignore air resistance. How much time elapses between the first ...
*October 9, 2014 by Mariah*

**Physics**

The ball spins at 7.7 rev/s. In addition, the ball is through with a linear speed of 19 m/s at an angle of 55 degrees with respect to the ground. If the ball is caught at the same height at which it left the quarterback's hand, how many revolutions has the ball made in the air...
*December 21, 2009 by Christopher*

**physics 203**

Water (p=1000kg/m^3) enters a pipe on the ground with an inside diameter of 2cm at a pressure of 4x10^5 Pa. Then a 1-cm diameter pipe leads the water to a height of 5m above the ground. The flow speed at the inlet is v1=1.5m/s. A) Find the flow speed at the outlet. B) Find the...
*April 9, 2013 by ash*

**physics**

Two children are playing on two trampolines. The first child can bounce 1.4 times higher than the second child. The initial speed up of the second child is 4.8 m/s. The maximum height of the second child is 1.17m and the initial speed of the first child is 5.66 m/s. How long ...
*September 29, 2011 by Brianna*

**math**

A passenger train travelled at an average speed of 72 km/h. A man on the passenger train observed a goods train, which was travelling at a speed of 54 km/h, in the on-coming direction. If the goods train passed him in 10 seconds, find the length of the goods train. Is it ...
*September 3, 2012 by Im*

**physic**

You are traveling at a constant speed υM, and there is a car in front of you traveling with a speed υA You notice that υM>υA, so you start slowing down with a constant acceleration a when the distance between you and the other car is x. What relationship...
*September 29, 2013 by kolam*

**Physics**

A 4kg and a 2kg block are moving along a horizontal frictionless surface. The 4 kg block is moving to the right with a speed of 6 m/s and the 2 kg block is moving to the left with a speed of 3 m/s. The two blocks collide inelastically and then continue to move together along ...
*November 17, 2009 by Jon Routh*

**phsyics **

A car races on a circular track of radius r. (a) Write an equation for the car's average speed when it travels a complete lap in time t. (b) The radius of the track is 100 m and the time to complete a lap is 14 s. Show that the average speed around the track is 45 m/s.
*March 19, 2014 by price *

**tangential speed and accelerations**

A helicoptor bladehas an angular speed of 6.50 rev/s and has an angular acceleration of 1.30 rev/s. point 1 on the blade is 3.00m and point 2 is 6.7m. Can you find the speeds of A) the tangential speeds and B) the tangential accelerations?
*October 12, 2010 by J*

**math(rational functions application)**

The average speed of a jet is 100km/h faster than a cargo plane. To travel 1400km, the cargo plane requires 25% more time than the jet. Find the average speed of the jet. This is the formula I figured out so far. V(average)=V(jet)-V(cargo 100km/h= d/t - d/t 100= [1400km/x] - [...
*October 22, 2009 by jane*

**calculus**

Boat A leaves the dock at 12pm heading due South at a constant speed of 20 km/h. Meanwhile, at 12pm Boat B, a pirate ship, is 15 km due West of the dock where boat A started, and is sailing due East at a constant speed of 15 km/h. If the pirates get within 10 km of another ...
*November 10, 2010 by Anya*

**Science**

Two satellites are launched at a distance R from a planet of negligible radius. Both satellites are launched in the tangential direction. The ﬁrst satellite launches correctly at a speed v0 and enters a circular orbit. The second satellite, however, is launched at a ...
*December 22, 2011 by Anonymous*

**math-pre calc**

On a drive from your home to town, you wish to average 48 mph. The distance from your home to town is 106 miles. However, at 53 miles (half way), you find you have averaged only 36 mph. What average speed must you maintain in the remaining distance in order to have an overall ...
*September 24, 2014 by liz*

**physics**

An m=150 g block hits an M= 265 g block initially at rest on a horizontal surface. After impact they stick together and slide 7.47 m before coming to rest. The coefficient of friction between blocks and surface is 0.39. a) What is in m/s the speed of both blocks immediately ...
*November 1, 2014 by Serena*

**Physics**

A golfer, standing on a fairway, hits a shot to a green that is elevated 5.50 m above the point where she is standing. The ball leaves her club at an angle of 37.0° above the ground, with a speed of 31.1 m/s. Find the time that the ball is in the air before it hits the green...
*February 1, 2015 by Tanner*

**Physics**

A golfer, standing on a fairway, hits a shot to a green that is elevated 5.50 m above the point where she is standing. The ball leaves her club at an angle of 37.0° above the ground, with a speed of 31.1 m/s. Find the time that the ball is in the air before it hits the green. ...
*February 2, 2015 by Paige*

**physics**

a gun,kept on straight horizontal ground is used to hit a car, traveling along the same road away from the gun with a uniform speed of 72km/h.The car is at a distance of 500m from the gun. when the gun is fired at an angle of 45 degrees with the horizontal. find (1) the ...
*May 25, 2016 by jabulani*

**Physics**

(a) If the maximum acceleration that is tolerable for passengers in a subway train is 1.52 m/s2 and subway stations are located 1030 m apart, what is the maximum speed a subway train can attain between stations? b)what is the travel time between stations? c)If a subway train ...
*September 3, 2009 by Nick*

**physics**

(a) If the maximum acceleration that is tolerable for passengers in a subway train is 1.52 m/s2 and subway stations are located 1030 m apart, what is the maximum speed a subway train can attain between stations? b)what is the travel time between stations? c)If a subway train ...
*September 4, 2009 by Nick*

**math**

A motorcycle leaves colorado springs, colorado, traveling north on I25 at an average speed of 47 mph. one hour later, a car leaves colorado springs, traveling south on I-25 at an average speed of 54 mph. How long after the motorcycle leaves will it take until they are 52 miles...
*March 5, 2013 by kelly*

**Intergated chemistry/physics**

A 10 pound bowling ball with a speed of 2.0 meters/second hits a 6 pound bowling ball. If the 10 pound bowling ball stops after the collision, what is the resulting speed of the 2nd ball in meters/second
*October 4, 2012 by Laura*

**science**

as the speed of a fluid increases the pressure decreases. as the speed of the fluid decreases, the pressure increases. what is this called?
*April 6, 2008 by troy*

**Physics**

Which of the following is not a good example of uniform circular motion? a) a person riding on a ferris wheel that is turning at a constant rate b) a person taking off on an airplane to fly around the world on a path defined by the equator c) a race car driving at a constant ...
*October 16, 2012 by Lewis*

**Physics**

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 12, 2009 by Robert C*

**physics**

Stickman is driving a dragster. He does the quarter mile in 4 seconds and at the finish line is speed is 100m/s. He deploys his parachute after he crosses the finish line and wished to slow to a speed of 10m/s in 10s. What diameter parachute does he need if the drag force is ...
*October 1, 2011 by Norman*

**physics**

Stickman is driving a dragster. He does the quarter mile in 4 seconds and at the finish line is speed is 100m/s. He deploys his parachute after he crosses the finish line and wished to slow to a speed of 10m/s in 10s. What diameter parachute does he need if the drag force is ...
*October 2, 2011 by Matt*

**physics**

A 10 g particle has the potential energy shown in a graph with the y-axis label U(J) and the x axis is labeled in cm. There is a diagonal line from 4 J down to 1 cm and the line levels out on the x axis to 3 cm and rises again to a height of 2 J at 5 cm and levels out to 7 cm ...
*December 2, 2009 by Ashley*

**Physics - 2-D kinematics**

A soccer ball is kicked with an initial horizontal velocity of 20 m/s and an initial vertical velocity of 16 m/s. I've calculated: Initial Speed: 25.61 m/s Angle: 38.66 degrees Maximum Height it reaches: 13.06 m Distance kicked: 65.29m NOW I NEED: What is the speed of the ball...
*February 3, 2012 by Anonymous*

**math (pre calc)**

Imagine that you are driving 150 miles and you want your average speed for the trip to be 60 miles per hour.Imagine that you drive the first half (by distance) of the trip at 50 mph. How fast must you drive on the second half to make your average speed for the whole trip 60 ...
*February 16, 2016 by Ray*

**projectile motion**

Two cars,A and B, are traveling in the sam direction, although car A is 208m behind car B. The speed of A is 24.4 m/s, and the speed of B ia 18.6m/s. How much time does it take for A to catch B? The answer is 208/5.8 which equals 35.8 seconds. Since displacement is equal to ...
*February 1, 2007 by leann*

**AP Physics**

A stone is tied to a string (length = 0.450 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, the circle is vertical. In the vertical case the maximum tension in ...
*October 26, 2010 by PLEASE HELP *

**AP PHYSICS**

A stone is tied to a string (length = 0.450 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, the circle is vertical. In the vertical case the maximum tension in ...
*October 27, 2010 by PLEASE HELP NEED IT PLEASE*

**Physics**

A rock is thrown vertically upward with a speed of 11.0 m/s from the roof of a building that is 70.0 m above the ground. Assume free fall. In how many seconds after being thrown does the rock strike the ground? GOT THIS!!!! t=5.07s What is the speed of the rock just before it ...
*September 11, 2006 by Josh*

**physics**

A car moving with constant acceleration covered the distance between two points 60.0 m apart in 6.00 s. Its speed as it passed the second point was 15.0 m/s. (a) What was the speed at the first point? (b) What was the magnitude of the acceleration? (c) At what prior distance ...
*September 10, 2011 by Rebekah*

**physic**

an enemy spaceship is moving toward your starfighter with a speed of 0.4c, as measured in your reference frame. The enemy ship fires a missile toward you at a speed of 0.7c relative to the enemy ship. If you measure the enemy ship to be 8.0 x 10^6 km away from you when the ...
*May 13, 2013 by yanis*

**physics**

A person is standing on and facing the front of a stationary skateboard while holding a construction brick. The mass of the person is 89.0 kg, the mass of the skateboard is 4.10 kg, and the mass of the brick is 2.50 kg. If the person throws the brick forward (in the direction ...
*January 15, 2015 by Anonymous*

**Physics**

The game is called Ice Bocci. You play by sliding pucks across the ice into each other, sort of like marbles. One player slides the red puck straight into a stationary green puck. The red puck is sliding with a speed of 4 m/s and weighs twice as much as the green puck. What ...
*March 20, 2011 by Paige*

**physics**

During a track event two runners, Mary, and Alice, round the last turn and head into the final stretch with Mary a distance d = 4.0 m in front of Alice. They are both running with the same speed of v0= 7.0 m/s. When the finish line is a distance L= 45.0 m away from Alice, ...
*September 11, 2013 by tini*

**anonymous**

I need help solving these problems. I tried but my teacher did not teach it to us so it is very difficult for me. Thanks. "Projectiles launched at an angle" 1. A golfer can hit a golf ball a horizontal distance of over 300 m on a good drive. What maximum height will a 301.5 m ...
*October 25, 2006 by PHYSICS.....confused*

**Phisics (Urgent)!!!!!!!!!!!!!!!!!!!!!!**

Consider a rocket in space that ejects burned fuel at a speed of vex= 1.5 km/s with respect to the rocket. The rocket burns 8 % of its mass in 280 s (assume the burn rate is constant). (a) What is the speed v of the rocket after a burn time of 140.0 s? (suppose that the rocket...
*December 8, 2013 by Anonimus*

**ALGEBRA 2**

A plane takes off from an aiport and flies east at a speed of 350 mi/h. Ten minutes later, a second plane takes off from the same airport and flies east at a higher altitude at a speed of 400 mi/h. How long does it take the second plane to overtake the first plane? I have ...
*August 16, 2009 by Emily*

**Physics**

When a high speed passenger train travelling at 161km/h rounds a bend,the engineer is shocked to see that a locomtive has improperly entered onto track from a siding and is a distance D=676m ahead.The locomotive is moving at 29km/h. The engineer of the high speed train ...
*September 13, 2008 by Waqas*

**Physics Help**

This is confusing me. I have to questions and I picked 2 answers but can someone tell me if I'm wrong and why? 1.)The distance an object travels per unit of time =a)Is its speed b)Is its velocity c)Is its acceleration 2.)The distance and direction an object travels per unit of...
*July 12, 2010 by Ariel*

**math **

If it takes 6 minutes to travel from Point A to Point B at a constant speed of 60 miles per hour, how many minutes does it take to travel the same route from point A to point B a constant speed of 50 miles per hour? I need an equation and a thorough/ clear explanation on how ...
*August 9, 2012 by anony*

**physics**

Two objects are connected by a light string passing over a light, frictionless pulley as in the diagram. m1 = 4.50 kg, m2 = 2.10 kg, and h = 4.30 m. The 4.50 kg object is released from rest at a point 4.30 m above the floor. Determine the speed of each object when the two pass...
*October 25, 2010 by Anonymous*

**calculus**

16. Given the following information, determine the constant speed, travel time, and cost that represent the minimum one-way trip delivery cost. Fuel costs per hour are equal to V^2/600 V is the speed in miles per hour Driver (labor) costs are $10 per hour One-way distance is ...
*May 8, 2013 by James*

**calculus**

16. Given the following information, determine the constant speed, travel time, and cost that represent the minimum one-way trip delivery cost. Fuel costs per hour are equal to V^2/600 V is the speed in miles per hour Driver (labor) costs are $10 per hour One-way distance is ...
*May 8, 2013 by James*

**science**

A British Concorde (BC) and a French Concorde (FC) flew in opposite directions around the earth (40 000 km). The BC covered half of its flight distance at a supersonic speed of 2500 km/h and the other half at a subsonic speed of 1000 km/h. The FC spent half of its flight time ...
*February 8, 2014 by king12*

**physics**

A person riding in the back of a pickup truck traveling at 60km/h on a straight, level road throws a ball with a speed of 10km/h relative to the truck in the direction of the truck's motion.What is the velocity of the ball relative to a stationary observer by the side of the ...
*February 9, 2014 by beti*

**Physics **

A child in danger of drowning in a river is being carried downstream by a current that has a speed of 2.35 km/hr. The child is 0.625 km from shore and 0.800 km upstream of a boat landing when a rescue boat sets out. If the boat proceeds at its maximum speed of 18.6 km/hr ...
*February 5, 2012 by Hoss*

**physics**

The cavle on an elevator is what pulls the elevator up, and allows it to come down safely. The mass of the elevator is 1400 kg. If the elevator starts from rest and is pulled upwards with a constant tension of 18 kN, what will its speed be after moving 6m? (Assume no ...
*October 7, 2007 by Anonymous*

**Physics**

You are driving down a highway at a speed of 20.0m/s when you spot a deer. You quickly slam on your brakes, trying to stop your car in front of the deer. Assume the braking force can be modeled as kinetic friction with a friction coefficient of 0.80. If the deer was 75.0m away...
*October 28, 2014 by K*

**Math HELP**

A man is walking at an average speed of 4 miles per hour alongside a railroad track. A freight train, going in the same direction at an average speed of 30 miles per hour, requires 5 seconds to pass the man. How long is the freight train? Give your answer in feet. What would ...
*October 5, 2010 by Amy*

**algebra**

Brandon starts running from the starting line of a track at a speed of 10 ft. per second. 60 seconds later david starts from the same point and runs in the same direction at a speed of 12 per second Let y represent brandons time and let x represent davids time. Write a system ...
*December 12, 2011 by Vianey*

**physics**

Two identical sources S1 and S2 are moving towards an observer P. The two sound sources S1 and S2 produce notes of frequency 500hz. If the speed of S1 and S2 are 20ms-1 and 23ms-1 respectively, calculate the beat frequency heard by P. (Speed of sound = 340ms-1) I don't ...
*October 16, 2015 by shu yan*

**physics**

Two friends, Al and Jo, have a combined mass of 171 kg. At an ice skating rink they stand close together on skates, at rest and facing each other, with a compressed spring between them. The spring is kept from pushing them apart, because they are holding each other. When they ...
*January 25, 2012 by Jen*

**physics**

A rock dropped from a small bridge encounters no air resistance and hits the pond below 1.0 s later. If it had been thrown horizontally with a speed of 10 m/s, then it would have hit the water A. more than 1.0 {s} later, since it has a greater distance to travel. B. 1.0 {s} ...
*January 25, 2011 by mely*

**Pre-Calculus**

I'm having trouble with this question. The number of horse-power H required to overcome wind drag on a certain automobile is approximated by: H(x)= 0.002(x)^2 + 0.005(x) - 0.029, [10 is less then/equal to (x) is less then/equal to 100]. Where x is the speed of the car in miles...
*February 8, 2011 by Sam*

**physics**

Billiard ball A of mass m_A = 0.130 kg moving with speed v_A = 2.50 m/s strikes ball B, initially at rest, of mass m_B = 0.145 kg. As a result of the collision, ball A is deflected off at an angle of 31.0 degree, with a speed v_A1 = 2.05 m/s. Write down the equation expressing...
*April 24, 2012 by Caylee*

**Phizzics....**

The Canadian microsatellite MOST (Microvariability and Oscillations of Stars) has a mass of just 52 kg. It travels in an almost circular orbit at an average altitude of 820 km above Earth’s surface. a) Calculate the gravitational force between Earth and the MOST satellite at ...
*May 15, 2012 by dreamygirl*

**Trig/Pre-Calc...**

Please help me with this. The finishing time for a runner completing the 200-meter dash is affected by the tail-wind speed, s. The change, t, in a runner's performance is modeled by the function shown below: t= 0.0119s^2 - 0.308s - 0.0003 Predict the change in a runner's ...
*October 23, 2014 by AbelovedAngel*

**phys**

A small metal cylinder rests on a circular turntable that is rotating at a constant speed. The small metal cylinder has a mass of 0.20kg, the coefficient of static friction between the cylinder and the turntable is 0.080, and the cylinder is located 0.15m from the center of ...
*September 25, 2009 by Chelsea*

**Physics**

A small metal cylinder rests on a circular turntable that is rotating at a constant speed. The small metal cylinder has a mass of 0.20kg, the coefficient of static friction between the cylinder and the turntable is 0.080, and the cylinder is located 0.15m from the center of ...
*September 28, 2009 by Tiffany*

**Analytical Mechanics**

a gun is fired with muzzle velocity v0 = 1000 m/s straight up along the z-axis. While moving through the air the Earth's gravity pulls on the bullet, which has mass m = 20 grams and the bullet's air resistance force can be approximated by the relationship Fresist = -cv^2 where...
*October 20, 2015 by Ryan*

**math**

drove from rich to boston at avg speed of 50 mph,if it took 5 hrs to drive from rich to phila at an avg speed of 70 mph and if the whole trip took 13 hrs how far is it from phila to boston?
*August 25, 2010 by Bob*

**physic**

a mass 2.9kg object moving at a speed of 5.9m\s sticks a mass 0.88kg object initially at rest. immeditaly after the collision the 2.9kg object has a velocity of 0.99m/s directed 27 degree from its initial line of motion. that is the speed of the 0.88kg mass immeditaly after ...
*February 26, 2011 by Anonymous*