Saturday

August 1, 2015

August 1, 2015

Number of results: 22,164

**physics**

A passenger on a moving train tosses a coin with an initial velocity of (-2.25 m/s)x unit vector + 4.26 m/s)y unit vector (from the point of view of the passenger). The train's velocity relative to the ground is (11.5 m/s)x unit vector. (a) What is the minimum speed of the ...
*September 16, 2012 by grace*

**physics**

1. Calculate the frequency (Hz) and energy (eV) of green photons with wavelength of 555nm. Photon energy = hν, where ν = frequency in Hz and h = 6.626x10-34 joule-sec, the Planck’s constant. Keep in mind that: wavelengthxfrequency = speed. 2. Andy Ruddick can serve ...
*March 1, 2009 by JeFF*

**Physics**

1) A fish jumps out of the water with a speed of 6.36 m/s. If the fish is in a stream with water speed = to 1.5 m/s, how high can the fish jump if it leaves the water traveling vertically upwards relative to the earth? 2)A ball is thrown by someone on a train moving at 10 m/s ...
*September 9, 2008 by Anne*

**Physics**

An airplane has a velocity of 454 km/h relative to the moving air. At the same time, a wind blows northward with a speed of 99 km/h relative to earth. The airplane is moving in an easterly direction relative to earth. Find the speed of the airplane to relative to earth. So, i ...
*October 1, 2010 by Jon*

**physics**

A 200-m-wide river flows due east at a uniform speed of 4.9 m/s. A boat with a speed of 9.0 m/s relative to the water leaves the south bank pointed in a direction 33o west of north. What is the (a) magnitude and (b) direction of the boat's velocity relative to the ground? Give...
*January 26, 2011 by jr*

**Physics**

James and Steve have a contest to see who can kick a football further. James kicks the football at an angle up of 57 degrees, and a speed of 75m/s. Steve kicks the ball with a speed of 100m/s, at an angle up of 48 degrees? Who wins the contest? Please show what each variable ...
*June 21, 2011 by Molly*

**school of engineering**

police officer in a patrol car parked in a70km/h observes a passing auto mobile travelling at a slow constant speed believing that of the automobile might be intoxicated the officer starts his car accelerate uniformly to 9km/h in 8s.and maintaining a constant velocity of 90km/...
*October 17, 2013 by khabat*

**algebraic reasoning**

the relationship b/w the distance d, in feet, required to stop a vehicle and s, the speed in miles per hour that the vehicle was traveling, is given by the equation d=0.0155s(squared)/f f represents the coefficient of friction b/w the tires and the road *it took a car 205 feet...
*February 23, 2008 by megan*

**physics**

On a pleasure cruise a boat is traveling relative to the water at a speed of 4.8 m/s due south. Relative to the boat, a passenger walks toward the back of the boat at a speed of 1.3 m/s. (a) What is the magnitude and direction of the passenger's velocity relative to the water...
*September 18, 2012 by manny*

**physics**

A downhill skier crosses the finishing line at a speed of 30 1 ms − and immediately starts to decelerate at 10 m s − 2 . There is a barrier 50 metres beyond the finishing line. (a) Find an expression for the skier’s speed when she is V metres beyond the finishing ...
*July 24, 2014 by Triana*

**physics**

A 11.6 kg weather rocket generates a thrust of 215.0 N. The rocket, pointing upward, is clamped to the top of a vertical spring. The bottom of the spring, whose spring constant is 399.0 N/m, is anchored to the ground. Initially, before the engine is ignited, the rocket sits at...
*November 1, 2009 by Anonymous*

**phy**

A blue ball is thrown upward with an initial speed of 20.6 m/s, from a height of 0.8 meters above the ground. 2.5 seconds after the blue ball is thrown, a red ball is thrown down with an initial speed of 8.2 m/s from a height of 23.7 meters above the ground. The force of ...
*September 13, 2011 by a*

**physics**

The power needed to accelerate a projectile from rest to its launch speed v in a time t is 48.0 W. How much power is needed to accelerate the same projectile from rest to a launch speed of 2v in a time of 1/2t
*October 10, 2011 by Acceleration*

**physics**

You are walking along Main street one afternoon. At 1 PM you are 50 meters east of the intersection of Main and Elm streets. You walk due east for 30 seconds, ending up 80 meters east of the intersection of Main and Elm. You then make a left turn and walk due north for 30 ...
*August 25, 2013 by Anonymous*

**math**

andys average driving speed for a 4-hour trip was 45 miles per hour. during the first 3 hours he drove 40 miles per hour. what was his average speed for the last hour of his trip? The trip length was 4 x 45 = 180 miles. He went 3x40 = 120 the first three hours. How many miles ...
*April 28, 2007 by anonymous*

**physic**

A student on a piano stool rotates freely with an angular speed of 3.07 rev/s. The student holds a 1.38 kg mass in each outstretched arm, 0.759 m from the axis of rotation. The combined moment of inertia of the student and the stool, ignoring the two masses, is 4.72 kg·m2, a ...
*March 25, 2010 by Mary*

**physics**

a jet pilot takes his aircraft in a vertical loop. a) if the jet is moving at a speed of 2000 km/h at the lowest point of the loop, determine the minimum radius of the circle so that the centripetal acceleration at the lowest point does not exceed 6.0g's b) calculate also the ...
*October 4, 2009 by jeffery*

**physics**

A cork gun contains a spring whose spring constant is 11.0 N/m. The spring is compressed by a distance DX = 9.8 cm and used to propel a cork of mass 6.60 g from the gun. Assuming the cork is released when the spring passes through its equilibrium position (Xeq), what is the ...
*December 10, 2011 by leav*

**PHYSICS**

A mass on a frictinless inclined ramp is connected to a rope with tension T. Complete the senteces with correct selection: -increases -decreases -stays the same a) If the block is moving up the ramp and theta=30 deg, its speed initally _________ if T=(mg)/2 b) If the block is ...
*September 30, 2007 by Lily*

**Physics**

A 59-kg housepainter stands on a 16-kg aluminum platform. The platform is attached to a rope that passes through an overhead pulley, which allows the painter to raise herself and the platform. (Ignore the mass of the pulley and any friction in the pulley.) (a) With what force ...
*October 4, 2012 by Madi*

**Physics (verification)**

I would love for someone to please verify my solution for this problem: A former amusement park attraction consisted of a huge vertical cylinder rotating rapidly around its axis. The rotation speed should be sufficient for the people found inside to be stuck to the wall when ...
*December 9, 2011 by Greg*

**Physics (verification)2**

I would love for someone to please verify my solution for this problem: A former amusement park attraction consisted of a huge vertical cylinder rotating rapidly around its axis. The rotation speed should be sufficient for the people found inside to be stuck to the wall when ...
*December 10, 2011 by Greg*

**Physics**

A 10.2 kg weather rocket generates a thrust of 200N. The rocket, pointing upward, is clamped to the top of a vertical spring. The bottom of the spring, whose spring constant is 500N/m, is anchored to the ground. a) Initially before the engine is ignited, the rocket sits at ...
*November 25, 2010 by Alexandra*

**Physics**

A 930 kg sports car collides into the rear end of a 2500 kg SUV stopped at a red light. The bumpers lock, the brakes are locked, and the two cars skid forward 2.6 m before stopping. The police officer, knowing that the coefficient of kinetic friction between tires and road is...
*October 24, 2010 by Eden*

**Physics**

Suppose that high-speed stroboscopic photographs show that the 200-g head of a golf club travels at 51 m/s just before it strikes a 50-g golf ball initially at rest on a tee. If the club head slows to at 36 m/s (in the same direction) after the collision, what is the speed of ...
*November 21, 2010 by help!*

**Physics**

Suppose that high-speed stroboscopic photographs show that the 200-g head of a golf club travels at 51 m/s just before it strikes a 50-g golf ball initially at rest on a tee. If the club head slows to at 36 m/s (in the same direction) after the collision, what is the speed of ...
*November 21, 2010 by help!*

**Physics**

Water flowing through a garden hose of diameter 2.77 cm fills a 25.0-L bucket in 1.40 min. (a) What is the speed of the water leaving the end of the hose? Answer in m/s (b) A nozzle is now attached to the end of the hose. If the nozzle diameter is one-third the diameter of the...
*March 30, 2014 by Renee*

**Physics**

Water flowing through a garden hose of diameter 2.77 cm fills a 25.0-L bucket in 1.40 min. (a) What is the speed of the water leaving the end of the hose? Answer in m/s (b) A nozzle is now attached to the end of the hose. If the nozzle diameter is one-third the diameter of the...
*March 30, 2014 by Renee*

**Physic**

Water flowing through a garden hose of diameter 2.77 cm fills a 25.0-L bucket in 1.40 min. (a) What is the speed of the water leaving the end of the hose? Answer in m/s (b) A nozzle is now attached to the end of the hose. If the nozzle diameter is one-third the diameter of the...
*March 30, 2014 by Renee*

**Physics**

A pipe that is open at both ends has a fundamental frequency of 330 Hz when the speed of sound in air is 333 m/s. What is the length of this pipe? Answer in units of cm. What is the second harmonic? What is the third harmonic? Answer in units of Hz. What is the fundamental ...
*October 1, 2012 by AJ*

**Physics**

A motorist drives for 150 km from City A to City B in 2.5 hr. He makes the return trip in 2.0 hr. Find (a) the average speed for each half of the trip, (b) the average velocity for each half of the trip, (c) the average speed of the entire trip, and (d) the average velocity ...
*June 16, 2014 by Piper*

**physics**

Cars A and B are racing each other along a straight path in following manner: Car A has head start and is a distance dA beyond starting line at t=0. The starting line is at x=o. Car A travels at constant speed vA. Car B starts at starting line but has better engine than car A ...
*September 27, 2009 by help*

**physics**

Cars A and B are racing each other along a straight path in following manner: Car A has head start and is a distance dA beyond starting line at t=0. The starting line is at x=o. Car A travels at constant speed vA. Car B starts at starting line but has better engine than car A ...
*September 27, 2009 by help*

**physics conservation of momentum**

A 0.5 kg ball is thrown horizontally towards a wall with a speed of 10 m/s. The initial velocity is chosen to be the positive x-direction for this question. The ball horizontally rebounds back from the wall with a speed of 10 m/s in the negative x-direction. What is momentum ...
*November 8, 2008 by rachel*

**Physics**

A 0.40-kg ball, attached to the end of a horizontal cord, is rotated in a circle of radius 1.3 m on a frictionless surface. If the cord will break when the tension in it exceeds 60 N, what is the maximum speed the ball can have? How would your answer be affected if there were ...
*December 24, 2010 by Matt*

**physics**

Question 4 A 0.9 kg block attached to a spring of force constant 2.1 N/m oscillates with an amplitude of 9 cm. A)Find the maximum speed of the block. Answer in units of m/s B)Find the speed of the block when it is 4.5 cm from the equilibrium position. Answer in units of m/s C)...
*November 29, 2012 by maura *

**Physics - Sound**

A sound wave travels in air at a frequency of 500 Hz. If part of the wave travels from air into water, does its frequency change? Does its wavelength change? Note that the speed of sound in air is about 340 m/s, whereas the speed of sound in water is about 1500 m/s.
*January 26, 2009 by Sam*

**physics**

A flywheel rotates at a constant angular acceleration. At time t = 1.38 s, it rotates with a speed of ω = 2.40 rad/s in the clockwise direction. At time t = 5.97 s, it rotates with a speed of ω = 2.40 rad/s in the counter-clockwise direction. What is its angular ...
*April 7, 2015 by winged17*

**physics**

A student stands at the edge of a cliff and throws a stone horizontally over the edge with a speed of 18m/s. The cliff is 50m above a flat horizontal beach, as shown in Figure 3.20. How long after being released does the stone strike the beach below the cliff? With what speed ...
*September 26, 2007 by Anonymous*

**Physics**

A cork gun contains a spring whose spring constant is 18.0 N/m. The spring is compressed by a distance ∆X = 6.0 cm and used to propel a cork of mass 7.66 g from the gun. Assuming the cork is released when the spring passes through its equilibrium position (Xeq), what is ...
*December 17, 2013 by Lina*

**Physics**

A cork gun contains a spring whose spring constant is 18.0 N/m. The spring is compressed by a distance ∆X = 6.0 cm and used to propel a cork of mass 7.66 g from the gun. Assuming the cork is released when the spring passes through its equilibrium position (Xeq), what is ...
*December 17, 2013 by Lina*

**physics**

water flows along a horizontal pipe of cross-sectional area 48cm^2 which has a constriction of cross-sectional area 12cm^2 at one place. If the speed of the water at the constriction is 4 m/s, calculate the speed in the wider section. The pressure in the wider section is 1.0 x...
*March 26, 2010 by Edwin*

**physics**

water flows along a horizontal pipe of cross-sectional area 48cm^2 which has a constriction of cross-sectional area 12cm^2 at one place. If the speed of the water at the constriction is 4 m/s, calculate the speed in the wider section. The pressure in the wider section is 1.0 x...
*March 26, 2010 by Edwin*

**physics**

You are on an airplane traveling 30° south of due west at 130.0 m/s with respect to the air. The air is moving with a speed 31.0 m/s with respect to the ground due north. 1) What is the speed of the plane with respect to the ground? 2) What is the heading of the plane with ...
*September 10, 2012 by ali*

**College Physics**

Although they don’t have mass, photons—traveling at the speed of light—have momentum. Space travel experts have thought of capitalizing on this fact by constructing solar sails—large sheets of material that would work by reflecting photons. Since the momentum of the photon ...
*October 13, 2013 by Kimmy*

**MITx: 8.01x Classical Mechanics**

Mary wants to throw a can straight up into the air and then hit it with a second can. She wants the collision to occur at height h=10.0 m above the throw point. In addition, she knows that she needs t1=4.0 s between successive throws. Assuming that she throws both cans with ...
*September 16, 2013 by simonsay*

**physics**

(a) How high a hill can a car coast up (engine disengaged) if friction is negligible and its initial speed is 78.0 km/h? m (b) If, in actuality, a 750 kg car with an initial speed of 78.0 km/h is observed to coast up a hill to a height 12.0 m above its starting point, how much...
*August 4, 2014 by mike*

**Physics**

A golfer tees off on level ground, giving the ball an initial speed of 46.5 m/s and an initial direction of 37.5 above the horizontal. a) how far from the golfer does the ball land? b) the next golfer in the group hits a ball with the same initial speed but at an angle above ...
*September 18, 2013 by Gabby*

**physics**

A,1.5kg,object,moves,up,the,y,axis,at,a,constant,speed.When,it,reaches,the,origin,the,force,F1=5.0N,at,37,deg,above,the,+x,axis,F2,=2.5N,in,the,+x,direction,F3=,3,5N,at,45,deg,below,the,neg,x,axis,and,F4,=,1.5N,in,the,neg,y,direction,are,applied,to,it,(a)Will,the,object,...
*January 19, 2008 by melissa*

**physics**

Gayle runs at a speed of 8.00 m/s and dives on a sled, initially at rest on the top of a frictionless, snow-covered hill, that has a vertical drop of 14.0 m. After she has descended a vertical distance of 5.00 m, her brother, who is initially at rest, hops on her back, and ...
*October 21, 2012 by Anonymous*

**science**

The speed of a bullet as it travels down the barrel of a rifle toward the opening is given by v = (-4.25 10^7) t^2 + (3.45 10^5) t, where v is in meters per second and t is in seconds. The acceleration of the bullet just as it leaves the barrel is zero. (a) Determine the ...
*January 22, 2015 by Anonymous*

**Centrifulag pump curve**

Q4 The system on site is a pressure sand filter, with a service curve. The filter is backwashed using the feed pump, at a higher flow rate, shown as backwash curve. Service duty point : 3 m3/h Backwash duty point : 9 m3/h Part (a) (4 marks) What is the speed of the pump to ...
*January 29, 2014 by Tony*

**Physics**

A car is doing a loop-the-loop. The loop has a radius of .4m. Assume the car is starting with the minimum speed it needs in order to stay in contact with the track at all times (at the top of the track, the car is not applying a force to the track). neglect friction. What is ...
*March 6, 2012 by Melissa*

**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 at a constant speed of 50 miles per hour?
*July 11, 2012 by Samantha*

**Math**

If 60 miles per hour is equivalent to a speed of 88 feet per second, express a speed of 45 miles per hour in feet per second. feet/sec
*May 18, 2008 by Mike*

**physics**

A 0.59 kg rubber ball has a speed of 1.50 m/s at point A and kinetic energy of 7.0 J at point B. (a) Determine the ball's kinetic energy at A Correct: Your answer is correct. J (b) Determine the ball's speed at B
*December 3, 2014 by kelly*

**physics**

hi,need help please.thank. A car is designed to get its energy from a rotating flywheel (solid disk) with a radius of 2.00 m and a mass of 525 kg. Before a trip, the flywheel is attached to an electric motor, which brings the flywheel's rotational speed up to 4000 rev/min. (a...
*November 22, 2009 by Chan*

**physics**

In outer space two identical space modules are joined together by a 500.0 massless cable. These modules are rotating about their center of mass. In each module, the cable is connected to a motor,so that the modules can pull each other together. The initial tangential speed of ...
*June 2, 2011 by Samantha*

**phys2**

A 60-kg astronaut is in space, far from any objects that would exert a significant gravitational force on him. He would like to move toward his spaceship, but his jet pack is not functioning. He throws a 720-g socket wrench with a velocity of 5 m/s in a direction away from the...
*March 17, 2012 by opp*

**nova**

7) You throw a 12-N stone vertically into the air from ground level. You observe that when it is 15.0 m above the ground, it is traveling at 25.0 m/s upward. Use the work –energy theorem to find (a) the stone’s speed just as it left the ground and (b) its maximum height. 8) A ...
*September 20, 2014 by papy*

**Physics**

A small block on a frictionless horizontal surface has a mass of 2.50×10−2 Kg. It is attached to a massless cord passing through a hole in the surface. The block is originally revolving at a distance of 0.300 m from the hole with an angular speed of 1.75 rad/s. The cord ...
*November 7, 2007 by Christina*

**Physics**

A missile launcher, mass M, at rest on a horizontal track fires a missile, mass m, horizontally. a) If the launch speed of the missile is v o , what (effective) coefficient of (kinetic) friction is required in order to stop the launcher within x meters? (b) Missile launcher ...
*August 8, 2012 by Chad*

**Physics**

A missile launcher, mass M, at rest on a horizontal track fires a missile, mass m, horizontally. a) If the launch speed of the missile is v o , what (effective) coefficient of (kinetic) friction is required in order to stop the launcher within x meters? (b) Missile launcher ...
*August 7, 2012 by Chad*

**mechanics**

Q3. A skeet (a small disc) of massM is fired at an angle to the horizontal with a speed v0. When it reaches the maximum height it is hit from below by a pellet of mass m (m < M) traveling vertically upward at a speed of v. The pellet is embedded in the skeet. (a) What is ...
*December 9, 2010 by sana*

**physics waves transverse longitudinal**

i real stuck on this and i really want explanations please. in which sprind do transverse waves travel faster, small diameter spring or slinky? i think this be the transverse waves but i not know how to explain why. in which spring do longitudinal waves travel faster? i think ...
*January 9, 2012 by Shreya*

**Physics (Algebra-based)**

A block starts at rest and slides down a frictionless track except for a small rough area on a horizontal section of the track.It leaves the track horizontally, flies through the air, and subsequently strikes the ground. gravity= 9.81 m/s^2. height1=4.1m---- is initially ...
*April 6, 2013 by Becky*

**Health**

Justine would like to improve her speed while dribbling the soccer ball from the defensive to the offensive side of the field. Justine can develop her speed for this type of activity by practicing · moving the ball close to her foot with control from one end of the field to ...
*December 31, 2013 by Steve*

**Physics**

Under what conditions can a quadratic function be a perfect square? Also.. A stone is thrown vertically upward at a speed of 40m/s. How long does it take to reach a height of 90m? I ended up with a quadratic of t^2-8t+18 which cannot be factored...So is the answer that the ...
*February 19, 2008 by Anonymous*

**Physics**

Under what conditions can a quadratic function be a perfect square? Also.. A stone is thrown vertically upward at a speed of 40m/s. How long does it take to reach a height of 90m? I ended up with a quadratic of t^2-8t+18 which cannot be factored...So is the answer that the ...
*February 19, 2008 by Anonymous*

**physics**

A child in danger of drowning in a river is being carried downstream by a current that has a speed of 2.10 km/h. The child is 0.600 km from shore and 0.800 km upstream of a boat landing when a rescue boat sets out. (a) If the boat proceeds at its maximum speed of 19.0 km/h ...
*October 28, 2012 by anusha*

**physics**

A mass m = 11.0 kg rests on a frictionless table and accelerated by a spring with spring constant k = 4979.0 N/m. The floor is frictionless except for a rough patch. For this rough path, the coefficient of friction is μk = 0.46. The mass leaves the spring at a speed v = 2...
*September 28, 2012 by hater of physics*

**Algebra I**

1. A Passenger train's speed is 60mi/h and a freight train's speed is 40mi/h. The passenger train travels the same distance in 1.5 h less time than the freight train. How long does each train take to make the trip? 2. Lois rode her bike to visit a friend. She traveled at 10 mi...
*October 9, 2007 by Wilford*

**Algebra 2**

how would you solve: the current in the river flowed at 3 mph. The boat could travel 24 mph downstream in half the time it took to travel 12 mi upstream. what was the speed of the boat in still water? please help. The time required to go any distance upstream a distance L is L...
*June 18, 2006 by Jonathan*

**Chem**

For a photon with = 730 nm, determine its speed, frequency, energy, and color. For frequency the formula would be v=c/lambda 3.00x10^8/7.30x10^-7=2.19x10^14/s Speed c=(v)(lambda) C=(v)(lambda) C= (2.19x10^14/s)(1.37x10^-6)=3.00x10^8 I got the wavelength by doing the ...
*October 25, 2014 by Feather*

**physics**

(Requires calculus) Prove the relativistic work-energy theorem in one dimension. The force exerted on a particle is given not by F=ma, but F=dp/dt. Using the expression for the relativistic momentum of a particle p=γmv, integrate the force exerted on the particle over the...
*September 26, 2009 by kkke*

**Physics**

1.You are stuck on a cliff and want to know how far to the bottom. You drop a rock and time how long it takes to hit the ground. If the rock takes 10 seconds to hit the ground how high is the cliff? How fast was the rock going to impact? 2. You throw a plate off your roof with...
*March 22, 2012 by Anonymous*

**Physics Probelms ASAP**

Could you please check my work and help me with a couple. An airplane that flies at 100 km/h with a 10 km/h tailwind travels at 110 km/h relative to the ground. If it instead flies into a 10 km/h headwind, its groundspeed is : 110 km/h /2= 55 km/h The average speed of a horse ...
*August 29, 2007 by Soly*

**Physics**

A 250 g block is dropped onto a relaxed veritcal spring that has a spring constant of k=2.5 N/cm. The block becomes attached to the spring and compresses the spring 12 cm befor momentarily stopping. While the spring is being compressed, what work is done on the block by a) ...
*December 16, 2006 by Me*

**physics**

Cars A and B are racing each other along the same straight road in the following manner: Car A has a head start and is a distance Da beyond the starting line at t=0. The starting line is at x=0. Car A travels at a constant speed Va. Car B starts at the starting line but has a ...
*June 30, 2011 by mjLa*

**Math**

The average student enrolled in the 20-wk Court Reporting I course at the American Institute of Court Reporting progresses according to the rule below where 0 t 20, and N'(t) measures the rate of change in the number of words/minute dictation the student takes in machine ...
*April 9, 2014 by Vanessa*

**physics**

A disk of mass m is spinning freely at 6.22 rad/s when a second disk of identical mass, initially not spinning, is dropped on it so that their axes coincide. In a short time the two disks are corotating. (The two disks have the same radius.) (a) What is the angular speed of ...
*March 6, 2015 by alba*

**Physics Equations of Motion**

Along a straight road through town, there are three speed-limit signs. They occur in the following order: 66 , 31 , and 19 mi/h, with the 31 -mi/h sign located midway between the other two. Obeying these speed limits, the smallest possible time tA that a driver can spend on ...
*June 7, 2012 by Jackie*

**Physics**

An automobile and a truck start from rest at the same instant, with the automobile initially at some distance behind the truck. The truck has a constant acceleration of 2.15m/s2 , and the automobile an acceleration of 3.47m/s2 . The automobile overtakes the truck after the ...
*June 8, 2015 by David*

**Physics**

A river has a steady speed of 0.500 m/s.A student swims upstream a distane of 1.00 km and swims back to the starting point. If the student can swim at a speed of 1.20 m/s in still water, how long does the trip take? How much time is required in still water for the same length ...
*February 13, 2014 by Anonymous*

**math Help ASAP**

write and solve inequality 17. the speed limit of a highway is 55 miles per hour. a car is traveling at least 65 miles per hour. how many miles per hour m over the speed limit is the car traveling? A 55-m>equal to 65;m. eqaul to 10 B m+65< equal to 55; m < equal to -...
*October 21, 2014 by kathy *

**physics**

A 10000 car comes to a bridge during a storm and finds the bridge washed out. The 700 driver must get to the other side, so he decides to try leaping it with his car. The side the car is on is 24.0 above the river, while the opposite side is a mere 6.80 m above the river. The ...
*February 11, 2008 by samantha*

**Physics**

I listed the questions with my answers. Are the answers correct? Thanks. A railroad locomotive is a rest with its whistle shrieking, and then it starts moving toward you. a.) Does the frequency that you hear increase, decrease, or stay the same? The frequency of the waves ...
*October 17, 2009 by Mary*

**physics**

a shopper in a supermarket pushes a cart with a force of 35 n directed at an angle of 25 downward from the horizontal. the force is just sufficient to over come the various frictional force, so the cart moves at constant speed. what is the net work dont on the cart? why? the ...
*September 23, 2010 by physics help please!!!*

**Astrophysics**

You know M(r) = v^2r /G d = distance; s= speed Planet 1: d=2/s=120 Planet 2: d=4/s=60 Planet 3: d=9/s=40 Planet 4: d=16/s=30 Planet 5: d=36/s = 20 You use the distance and orbital speed of the first planet to determine the mass enclosed within the orbit of the first planet to ...
*October 29, 2008 by anonymous*

**Physics**

An open-topped tank completely filled with water has a release valve near its bottom. The valve is 1.75m below the water surface. Water is released from the valve to power a turbine, which generates electricity. The area of the top of the tank, AT, is 11.5 times the cross-...
*September 3, 2014 by Santi*

**physics**

The speed of a bullet as it travels down the barrel of a rifle toward the opening is given by v = (-4.25 107) t 2 + (3.45 105) t, where v is in meters per second and t is in seconds. The acceleration of the bullet just as it leaves the barrel is zero. (a) Determine the ...
*January 22, 2015 by Anonymous*

**physics**

A bullet with mass m = 5.21 g is moving horizontally with a speed v=367 m/s when it strikes a block of hardened steel with mass M = 14.8 kg(initially at rest). The bullet bounces o the block in a perfectly elastic collision. (a) What is the speed (m/s) of the block immediately...
*December 15, 2011 by Sarah*

**physics**

Traffic shock wave. An abrupt slowdown in concentrated traffic can travel as a pulse, termed a shock wave, along the line of cars, either downstream (in the traffic direction) or upstream, or it can be stationary. Figure 2-22 shows a uniformly spaced line of cars moving at ...
*October 10, 2011 by turk*

**physics i really need help :(**

A projectile is fired with an initial speed of 61.3m/s at an angle of 31.5° 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 covered (...
*November 24, 2012 by juanita*

**physics**

Two gears A and B are in contact. The radius of gear A is twice that of gear B. (a) when A’s angular velocity 6.00 Hz counter clockwise, what is B’s angular velocity? (b) If A’s radius to the tip of the teeth is 10.0 cm what is the linear speed of a point on the tip of a gear ...
*October 3, 2011 by John*

**math**

Two towns P and Q are 400 km apart. A bus left for P and Q. It stopped at Q for one hour and then started the return to P. one hour after the departure of the bus from P, a trail also heading for Q left P. the trailer met the returning bus ¾ of the way from P to Q. they met t ...
*March 14, 2015 by kudu*

**math**

Two towns P and Q are 400 km apart. A bus left for P and Q. It stopped at Q for one hour and then started the return to P. one hour after the departure of the bus from P, a trail also heading for Q left P. the trailer met the returning bus ¾ of the way from P to Q. they met t ...
*March 15, 2015 by kudu*

**general science**

2 waves are traveling through a container of nitrogen gas. Amplitude of the first wave is 0.3 cm, and the second 0.9 cm. What is true about the two waves? a. the energy of thee first wave is less than the second b. energy of the first wave is greater c. speed of the first wave...
*February 26, 2010 by Mike*

**physics help**

A 1100 kg automobile is at rest at a traffic signal. At the instant the light turns green, the automobile starts to move with a constant acceleration of 3.0 m/s2. At the same instant a 2800 kg truck, traveling at a constant speed of 8.0 m/s, overtakes and passes the automobile...
*March 26, 2010 by beav*

**Physics - sound waves**

I listed the questions with my answers. Are the answers correct? Thanks. A railroad locomotive is a rest with its whistle shrieking, and then it starts moving toward you. a.) Does the frequency that you hear increase, decrease, or stay the same? The frequency of the waves ...
*October 17, 2009 by Mary*