Sunday

February 7, 2016
**physics**

a spherical balloon of diameter 2m is filled with helium.Assume STP .how much is contained in the balloon helium
*Friday, May 1, 2015 by Anonymous*

**Physics**

Mass m2 rests on an incline and attaches to a string that goes over a pulley, where mass m1 hangs on the other side of the incline. Assume that there is no friction between m2 and the incline, that m2 = 5.1 kg, m1 = 0.9 kg, the radius of the pulley is 0.10 m, the moment of ...
*Friday, May 1, 2015 by James*

**Physics**

If the current in a wire of a CD player is 1.10 mA, how long would it take for 3.40 C of charge to pass a point in this wire?physi
*Thursday, April 30, 2015 by Chris *

**Physics**

Update: Planets are not uniform inside. Normally, they are densest at the center and have decreasing density outward toward the surface. Model a spherically symmetric planet, with the same radius as the earth, as having a density that decreases linearly with distance from the ...
*Thursday, April 30, 2015 by Katie*

**Physics**

Two electrostatic point charges of +60.0 μC and +57.0 μC exert a repulsive force on each other of 161 N. What is the distance between the two charges? The value of the Coulomb constant is 8.98755 × 109 N · m2/C2. Answer in units of m.
*Thursday, April 30, 2015 by Chris *

**physics**

four equal charges 2*10^-6c each are fixed at the four corner of a square of side 5cm.find the coulumb force experinced by one of the charge due to rest three
*Thursday, April 30, 2015 by nikhil gupta*

**physics**

four equal charges 2*10^-6c each are fixed at the four corner of a square of side 5cm.find the coulumb force experinced by one of the charge due to rest three
*Thursday, April 30, 2015 by nikhil*

**Physics**

The lens and mirror in the figure below are separated by d = 1.00 m and have focal lengths of +74.8 cm and -42.2 cm, respectively. An object is placed p = 1.00 m to the left of the lens as shown.
*Thursday, April 30, 2015 by Austin*

**physics**

just a question out of curiosity... Why is it that when you stretch a rubber band between your thumbs the same length both sides of the rubber band make two different sounds? Is it because the sound waves are at different velocities or frequencies?
*Thursday, April 30, 2015 by jake*

**SOLVE -MATH**

A physics exam consists of 9 multiple choice questions and 6 open-ended problems in which all work must be shown.If an examinee must answer 6 of the multiple- choice questions and 3 of the open-ended problems, in how many ways can the questions and problems be chosen?
*Thursday, April 30, 2015 by JORDAN*

**physics**

2. An object is 20.0 cm from a converging lens, and the image falls on a screen. When the object is moved 4.00 cm closer to the lens, the screen must be moved 2.70 cm farther away from the lens to register a sharp image. Determine the focal length of the lens.
*Thursday, April 30, 2015 by tasha*

**Physics**

An X-ray tube used for cancer therapy oper- ates at 8.8 MV with a beam current of 19 mA striking a metal target. Calculate the power of this beam.
*Thursday, April 30, 2015 by Chris*

**Physics**

A racket exerted an average force of 152.0 N on a ball initially at rest. If the ball has a mass of 0.070 kg and was in contact with the racket for 0.030 s, what was the kinetic energy of the ball as it left the racket?
*Thursday, April 30, 2015 by Maria*

**Physics**

A net charge of 73 mC passes through the cross-sectional area of a wire in 9 s . What is the current in the wire? The fun- damental charge is 1.602 × 10−19 C.
*Thursday, April 30, 2015 by Chris*

**MATH**

A physics exam consists of 9 multiple choice questions and 6 open-ended problems in which all work must be shown.If an examinee must answer 6 of the multiple- choice questions and 3 of the open-ended problems, in how many ways can the questions and problems be chosen?
*Thursday, April 30, 2015 by STAR ---- HELP.....*

**physics**

Two +'ve charges separated by a distance 2m each other with a force of 0.36N. If the combined charge is 26mc , the charges are
*Thursday, April 30, 2015 by Thirumal*

**physics**

A football kicker can give the ball an initial speed of 25m/s. What are the greatest and least elevation angles at which he can kick the ball to score a field goal from a point 50m in front of goalposts whose horizontal bar is 3.44m above the ground?
*Thursday, April 30, 2015 by john*

**physics**

A stone is dropped from the top of a cliff which is 100m high. At the same time another stone is vertically thrown upwards from the foot of the cliff woth a speed of 40m/s.AT what height and when do the stones meet
*Thursday, April 30, 2015 by asgf*

**physics**

bull's-eye bob at a hunting range fires his rifle at a target 200 meters downrange. the bullet moves horizontally from the rifle barrel with a speed of 400 m/s? how far does the bullet drop from a straight line horizontal path bny the time it reaches the target
*Wednesday, April 29, 2015 by Anonymous*

**physics**

A 16lb block rests on a horizontal frictionless surface. A cord attached to the block, running horizontally, passes over a pulley whose diameter is 6in, to a hanging block weighing 16lb. The system is released from rest, and the blocks are observed to move 8.1ft in 5s. What is...
*Wednesday, April 29, 2015 by I Don't Know*

**physics**

A smooth body slides down a plane inclined at an angle of 60degree to the horizontal calculate, A. The components of the acceleration of the body. B. Along the inclined plane. C. Perpendicular to the plane. D. The velocity of the body at the base of the plane after 10s. E. The...
*Wednesday, April 29, 2015 by Marino*

**PHYSICS**

A particle (mass = 5.0 g, charge = 40 mC) moves in a region of space where the electric field is uniform and is given by Ex = 2.5 N/C, Ey = Ez = 0. If the velocity of the particle at t = 0 is given by vy = 50 m/s, vx = vz = 0, what is the speed of the particle at t = 2.0 s?
*Wednesday, April 29, 2015 by Mary*

**physics**

A tennis ball is thrown vertically upwards from the ground with a velocity of 50m/s calculate.1.the maximum height reached. 2.the time to reached the maximum height. 3.the time of flight
*Wednesday, April 29, 2015 by Marino*

**Physics**

What is the velocity of an object that is dropped from a height of 20m,just before it reaches the ground?
*Wednesday, April 29, 2015 by Anonymous*

**physics**

a diver of mass 101 kg jumps upward off a diving board into water. Diving board is 6m above water. Driver has a speed of 1.2m/s. based on speed how high above the board will she rise?
*Wednesday, April 29, 2015 by danaja*

**chemistry**

Table of enthalpy of solution for selected cesium salts Compound and ΔsolH kJ mol-1: - Cesium bromide: 25.98 - Cesium iodide: 33.35 - Cesium chloride: 17.78 - Cesium fluoride monohydrate: -10.46 - Cesium fluoride sesquihydrate (·1.5H2O): -5.44 Data taken from CRC ...
*Wednesday, April 29, 2015 by john*

**physics**

A uniform plank of seesaw is 5meter long.a boy weighing40kgf sits 1.5meter from the one end.what will be the distance of a girl weighing 25kgf sit at other end,so as to balance the seesaw.
*Wednesday, April 29, 2015 by nitesh srivastava*

**physics**

two charges of equal magnitude are 25.5 cm apart if the force between the charges is 155 N what is the magnitude of the charges
*Tuesday, April 28, 2015 by j*

**Physics Help Please! Decay Questions**

archaeologist digging at the site of an ancient settlement discover the remains of a wooden structure. carbon 14 dating of the wood from the structure finds a decay rate of 180 decays/min. Knowing that the decay rate for living wood is 600 decays/min and the decay constant for...
*Tuesday, April 28, 2015 by Anonymous*

**Physics**

A satellite has a mass of 6445 kg and is in a circular orbit 4.14 × 105 m above the surface of a planet. The period of the orbit is 2.1 hours. The radius of the planet is 4.52 × 106 m. What would be the true weight of the satellite if it were at rest on the planet...
*Tuesday, April 28, 2015 by Sandra*

**Physics**

A car skidded on a roadway that has a coefficient of friction with the road of 0.7. A police officer measured the skid marks and noted them to be 100 feet long. Two years later at trial, the lawyer for the driver argues that the officer did not measure the skid marks correctly...
*Tuesday, April 28, 2015 by Hassan*

**Physics Help Please**

archaeologist digging at the site of an ancient settlement discover the remains of a wooden structure. carbon 14 dating of the wood from the structure finds a decay rate of 180 decays/min. Knowing that the decay rate for living wood is 600 decays/min and the decay constant for...
*Tuesday, April 28, 2015 by Anonymous*

**Physics**

Calculate the work required to pull a wagon along a horizontal road for 4.0x10^2 m at a constant speed of 3.0 m/s if the force of friction is 8.0 N.
*Tuesday, April 28, 2015 by Richard*

**Physics - Half Life Question Check!!!**

An ancient rock is found to contain 40Ar gas, indicating that 77% of the 40K in the rock has decayed since the rock solidified. Any argon would have boiled out of liquid rock. How long ago did the rock solidify? The half-life of 40K is 1.25 billion years. A) 2.6 billion years ...
*Tuesday, April 28, 2015 by Meli*

**Physics **

Microwaves travel at the speed of light, 3.00 × 108 m/s. When the frequency of microwaves is 5.93× 109 Hz, what is their wavelength? Answer in units of m.
*Tuesday, April 28, 2015 by Axel *

**PHYSICS PLEASE HELP**

A very large firecracker explodes in the hallway into 3 fragments. Physics students rush to the scene to enrich their knowledge of the law of conservation of momentum. They report that Fragment 1: mass=1.23kg, v=8.70m/s, north Fragment 2: mass =2.60kg,v=6.10m/s,east fragment 3...
*Tuesday, April 28, 2015 by Maddie *

**Physics please help **

He drops a ninja ball device from a height of 10.0m. The mass of the enter device is 190g and the mass of the top (smallest) ball is 2.90g A) calculate the momentum of the device as it hits the ground (ignore air resistance) I know that this answer is 2.66 for sure B) if the ...
*Tuesday, April 28, 2015 by Maddie *

**Physics **

Periodic waves spread out over the surface of a lake where two women, Jenna and Mel, are fishing in separate boats 97 meters apart. Each woman's boat bobs up and down 31/min. At a time when Jenna's boat is at a crest, Mel's boat is at its lowest point, and there ...
*Tuesday, April 28, 2015 by Anonymous*

**physics**

A mass is attached to a vertical spring, which then goes into oscillation. At the high point of the oscillation, the spring is in the original unstretched equilibrium position it had before the mass was attached; the low point is 8.6cm below this. What is the period of ...
*Tuesday, April 28, 2015 by Anonymous*

**physics**

A wheel is mounted on a frictionless axle. A cord is wrapped around the wheel and a mass, m= 10kg, is attached at the end of the cord.
*Tuesday, April 28, 2015 by titu*

**physics**

A solid ball with a mass m = 0.53 kg floats in a tank of water. The ball is made of material with a density of 400 . The density of water is 1000 . What fraction of the volume of the ball is below the waterline?
*Tuesday, April 28, 2015 by Anonymous*

**physics**

What fraction of the volume of the ball is below the waterline?
*Tuesday, April 28, 2015 by joseph*

**physics **

Vibrating a long spring with a succession of pulses with a frequency of 50hz produces adjecent nodes that are separated by 3.5cm. What is the velocity of the longitudinal waves formed?
*Tuesday, April 28, 2015 by Anonymous*

**PHYSICS**

A tube is open only at one end. A certain harmonic produced by the tube has a frequency of 500 Hz. The next higher harmonic has a frequency of 611 Hz. The speed of sound in air is 343 m/s. (a) What is the integer n that describes the harmonic whose frequency is 500 Hz? (b) ...
*Tuesday, April 28, 2015 by Anonymous*

**physics**

A rocket is fired with an initial velocity of 200m/s at an angle of 60' to the horizontal.Find (1)the maximum height reached.
*Tuesday, April 28, 2015 by sandra*

**Physics**

The equation of a transverse wave traveling in a string is given by y(x,t) = 10 cos (π/2)(0.0050x - 8.0t + 0.57), in which x and y are expressed in centimeters and t in seconds. Write down the equation of a wave which, when added to the given one, would produce standing ...
*Tuesday, April 28, 2015 by Nora*

**PHYSICS**

How do I solve this? A satellite has a mass of 5949 kg and is in a circular orbit 4.07 × 105 m above the surface of a planet. The period of the orbit is 1.9 hours. The radius of the planet is 4.55 × 106 m. What would be the true weight of the satellite if it were ...
*Monday, April 27, 2015 by Anonymous*

**Physics**

A 250kg car initially at rest was travelling with acceleration of 10m/s square. Calculate the kinetic energy after 3 seconds
*Monday, April 27, 2015 by Jeff*

**physics, doppler effect**

"A source of sound of frequency f0 moves horizontally at constant speed u in the x direction at a distance h above the ground. An observer is situated on the ground at the point x=0 (the source passes over this point at t=0). Show that the signal received at any time Tr ...
*Monday, April 27, 2015 by doppler effect*

**physics**

If the coefficient of kinetic friction between tires and dry pavement is 0.800, what is the shortest distance in which an automobile can be stopped by locking the brakes when traveling at 25.6m/s ?
*Monday, April 27, 2015 by Alkhanssa*

**physics**

A feather is dropped onto the surface of the moon. How far will the feather have fallen if it reaches the surface in 9.00 seconds? Given: g on moon = –1.63 meters/second
*Monday, April 27, 2015 by star*

**Physics**

A 20 C charge experiences a 2 N force in an electric field. What is the strength of the electric field?
*Monday, April 27, 2015 by Jennifer*

**Physics**

Two pellets, each with a charge of 1 microcoulomb, are located 3 cm apart. What is the electric force between them?
*Monday, April 27, 2015 by Ashley*

**Physics**

Can someone help me solve this? I've tried it a few times, but I keep getting answers that seem off. Like, for example, I'm getting 2.339 for part A, and it just seems completely off. So if you know the right formulas and can walk me through this, I'd appreciate it...
*Monday, April 27, 2015 by James*

**Physics**

An equal amount of heat is transferred to two containers containing water at the same temperature. If the second container contains three times as many water molecules as the first, how do the final temperatures compare?
*Monday, April 27, 2015 by Ashley*

**Physics**

The maximum speed of a 3.68-kg mass attached to a spring is 0.688 m/s, and the maximum force exerted on the mass is 11.6 N. What is the amplitude of motion for this mass? (in m) What is the force constant of the spring? (in N/m) What is the frequency of this system? (in Hz)
*Sunday, April 26, 2015 by Madison*

**Physics**

A large pendulum with a 200-lb gold-plated bob 12 inches in diameter is on display in the lobby of the United Nations building. Assume that the pendulum has a length of 78.4 ft. It is used to show the rotation of the Earth - for this reason it is referred to as a Foucault ...
*Sunday, April 26, 2015 by Madison*

**PHYSICS**

A satellite has a mass of 5949 kg and is in a circular orbit 4.07 × 105 m above the surface of a planet. The period of the orbit is 1.9 hours. The radius of the planet is 4.55 × 106 m. What would be the true weight of the satellite if it were at rest on the planet...
*Sunday, April 26, 2015 by Anonymous*

**PHYSICS**

How do I solve this? The blade of a windshield wiper moves through an angle of 90.0° in 0.453 s. The tip of the blade moves on the arc of a circle that has a radius of 0.775 m. What is the magnitude of the centripetal acceleration of the tip of the blade?
*Sunday, April 26, 2015 by KS*

**AP Physics **

Two adjacent natural frequencies of an organ pipe are found to be 900 Hz and 990 Hz. (a) Calculate the fundamental frequency and length of this pipe. other info that I already calculated: -the pipe is open at both ends - length of pipe is 1.89m
*Sunday, April 26, 2015 by Ayesha*

**physics**

A charge of -3.00 µC is fixed at the center of a compass. Two additional charges are fixed on the circle of the compass (radius = 0.115 m). The charges on the circle are -4.70 µC at the position due north and +5.00 µC at the position due east. What is the ...
*Sunday, April 26, 2015 by Anonymous*

**physics**

A charge of +3.7 ✕ 10-5 C is located at a place where there is an electric field that points due east and has a magnitude of 16400 N/C. What are the magnitude and direction of the force acting on the charge?
*Sunday, April 26, 2015 by Anonymous*

**physics**

The force of repulsion that two like charges exert on each other is 3.2 N. What will the force be if the distance between the charges is increased to 4 times its original value?
*Sunday, April 26, 2015 by Anonymous*

**physics**

A charge of -3.00 µC is fixed at the center of a compass. Two additional charges are fixed on the circle of the compass (radius = 0.115 m). The charges on the circle are -4.70 µC at the position due north and +5.00 µC at the position due east. What is the ...
*Sunday, April 26, 2015 by Anonymous*

**physics**

Consider three identical metal spheres, A, B, and C. Sphere A carries a charge of -6q. Sphere B carries a charge of -5q. Sphere C carries no net charge. Spheres A and B are touched together and then separated. Sphere C is then touched to sphere A and separated from it. Lastly...
*Sunday, April 26, 2015 by Anonymous*

**Physics**

An observer stands 25 m behind a marksman practicing at a rifle range. The marksman fires the rifle horizontally, the speed of the bullets is 840 m/s, and the air temperature is 20 °C. How far does each bullet travel before the observer hears the report of the rifle? ...
*Sunday, April 26, 2015 by Anonymous*

**physics**

Four resistors are connected to a battery with a terminal voltage of 18.0 V. The resistors are, R1=61, R2=34, R3=90, and R4=11. R1 & R2 are in series, and combined are in parallel with R3, & the combination of R1, R2, & R3 are in series with R4. Find the current in the 34.0 &#...
*Sunday, April 26, 2015 by allan*

**PHYSICS**

By accident, a large plate is dropped and breaks into three pieces. The pieces fly apart parallel to the floor. As the plate falls, its momentum has only a vertical component, and no component parallel to the floor. After the collision, the component of the total momentum ...
*Sunday, April 26, 2015 by Anonymous*

**PHYSICS**

How do I solve this? A mine car (mass=380 kg) rolls at a speed of 0.50 m/s on a horizontal track, as the drawing shows. A 170-kg chunk of coal has a speed of 0.92 m/s when it leaves the chute (at a 25 degree incline). Determine the speed of the car–coal system after the ...
*Sunday, April 26, 2015 by KS*

**PHYSICS**

How do I solve this? A 700-kg race car can drive around an unbanked turn at a maximum speed of 41 m/s without slipping. The turn has a radius of 190 m. Air flowing over the car's wing exerts a downward-pointing force (called the downforce) of 12000 N on the car. (a) What ...
*Sunday, April 26, 2015 by KS*

**physics**

Calculate the capacitance of a planet, assuming it is a spherical capacitor of radius R = 9050.0 km with charge distributed throughout the volume of the sphere.
*Sunday, April 26, 2015 by titu*

**PHYSICS**

How do I solve this? For the normal force in the drawing to have the same magnitude at all points on the vertical track, the stunt driver must adjust the speed to be different at different points. Suppose, for example, that the track has a radius of 2.87 m and that the driver ...
*Sunday, April 26, 2015 by KS*

**PHYSICS**

How do I solve this? Object A is moving due east, while object B is moving due north. They collide and stick together in a completely inelastic collision. Momentum is conserved. Object A has a mass of mA = 16.6 kg and an initial velocity of nu Overscript bar EndScripts ...
*Sunday, April 26, 2015 by KS*

**Physics**

In an exhibit at the NASA museum in Huntsville, AL, there is a “human centrifuge”. Guests stand upright against the walls of a circular room with a radius of 8 meters which then spins at an angular velocity ω about an axis through its center. Then, once the room...
*Sunday, April 26, 2015 by amanda*

**Physics**

A sports car with a very powerful engine driving on a surface with a coefficient of static friction µs = 0.8 and a ten degree incline wants to accelerate from a stop to 100 km/hr. (You may neglect air resistance.) a) What is the fastest that the car can accomplish this? ...
*Sunday, April 26, 2015 by ji*

**Physics**

A small block is attached to an ideal spring and is moving in SHM on a horizontal, frictionless surface. When the amplitude of the motion is 0.090m , it takes the block 2.68s to travel from x= 0.090m to x= -0.090m . If the amplitude is doubled, to 0.180m , how long does it ...
*Sunday, April 26, 2015 by Katie*

**Physics**

Two hikers, Alisha and Caleb, are resting on a hillside; the hill has a slope of 30 degrees, and Caleb is sitting above Alisha, eight meters away. They’ve brought fruit to eat on the trail, but they want to trade. a) Caleb throws an orange down to Alisha, with its initial...
*Sunday, April 26, 2015 by 0000*

**Physics**

The combination of an applied force produces a constant total torque of 39.6 N.m on a wheel rotating about a fixed axis. The applied force acts for 5.3 s. During this time, the angular speed of the wheel increases from 0 to 9.8 rad/s. Determine the moment of inertia of the wheel.
*Sunday, April 26, 2015 by Exes*

**Physics**

I shot two arrows into the air the first arrow had a speed of 10 m/sec , 1 second later I shot the 2nd arrow into the air with a speed of 15 m/sec. Will they meet? If so, where?
*Sunday, April 26, 2015 by Christian*

**Physics**

An equal amount of heat is transferred to two containers containing water at the same temperature. If the second container contains three times as many water molecules as the first, how do the final temperatures compare?
*Sunday, April 26, 2015 by Sean*

**Physics**

A liter of water is used to cool some electronics. If 1000 J of heat is given off by the electronics, by what temperature does the water increase? One liter of water has a mass of 1 kg and a specific heat of 4.184 J/(g °C). I can not get this..please help
*Sunday, April 26, 2015 by Sean*

**Engineering Physics 1**

I shot the first arrow Into the air with a speed of 10 m/sec , 1 second later I shot the 2nd arrow into the air with a speed of 15 m/sec. Will they meet? If so, where? how do i solve this?
*Sunday, April 26, 2015 by Joshua*

**physics**

If the time period of a wave is twice its frequency. How many waves are produced in 4secs if its frequency is 2hz
*Sunday, April 26, 2015 by zayeem*

**physics**

The figure above shows a chain being held on a table with one quarter of its length hanging over the edge. Friction is negligible. The chain has length L = 24 cm and mass m = 0.012 kg. Calculate how much work is required to pull the hanging section back onto the table.
*Saturday, April 25, 2015 by john*

**PHYSICS ANSWER CHECK**

A car can brake to a stop from 60mph in 2.6 seconds. If the car has a weight of 3225 lbs, what force in Newton's acts on the car. F=ma, vt=v0+at, a=(vt-v0)/t=(0-60mph)/2.6s=-23.1m/s^2 3225 lbs=1462.84 kg thus F=1462.84kg*(-23.1m/s^2)=-63.3N
*Saturday, April 25, 2015 by MJW*

**Physics**

In an empty rubber raft the pressure is approximately constant. You push on a large air pump that pushes 1.0 L(1.0× 10^−3m3) of air into the raft. You exert a 17N force while pushing the pump handle 3.0×10^−2m . Determine the work done on the gas. If ...
*Saturday, April 25, 2015 by Anonymous *

**PHYSICS answer check**

a gun converts 200J of stored energy into kinetic energy of the 0.02kg bullet. a)What is the speed of the bullet as it leaves the gun? b)If the gun is fired straight up, how high will the bullet go? a)200J b)m*g*h= (0.02kg)(10m/s^2)=200J h=100m
*Saturday, April 25, 2015 by MJW*

**PHYSICS answer check**

A 25 gram arrow fired from a bow has a speed of 80m/s. The energy in the arrow came from work done by the bow that acted over a 1m "draw" distance. What average force acted on the arrow over this distance mass=0.025kg speed=80m/s avg force 2N
*Saturday, April 25, 2015 by MJW*

**physics**

Which of the following is the correct unit of k in the equation of a damped harmonic oscillator given as , where b is the damping factor and all the symbols have their usual meaning? 2 If s is distance and t is time, what must be the dimensions of a and b in the equation...
*Saturday, April 25, 2015 by Cali franco*

**Physics**

A 4 kg block is placed on an incline at an angle of 30 degrees. If the coefficient of static friction is 0.3 and the coefficient of kinetic friction is 0.2 what is the net force on the block?
*Saturday, April 25, 2015 by Carolyn*

**Physics**

A sports car with a very powerful engine driving on a surface with a coefficient of static friction µs = 0.8 wants to accelerate from a stop to 100 km/hr. (You may neglect air resistance.) a) What is the fastest that the car can accomplish this? b) How far will the car ...
*Saturday, April 25, 2015 by ji*

**Science-Physics **

From what height was a brick dropped if it hit the ground with a speed of 4.3 m/s?
*Saturday, April 25, 2015 by Desirae*

**physics**

A body oscillates with simple harmonic motion along the x axis. Its displacement varies with time according to the equation x =5sin πt + π 3( ). The velocity of the body at t = 1.0 s is (-8 m sec )
*Saturday, April 25, 2015 by chris*

**Physics**

The temperature of a 1 m long aluminum rod is 20° C. If the temperature is increased to 70° C, what is the length of the rod? The coefficient of linear expansion for aluminum is 16 * 10^-6 /(degrees)C Please help I can not get this.
*Saturday, April 25, 2015 by Anonymous*

**physics**

a mass of 9.6 kg is moving horizontally as a force of 2.3 N , directed at 21° below the horizontal , is exerted on it , when the speed is 7.9 m/s, what is the rate at which the force is doing work
*Saturday, April 25, 2015 by riham *

**physics**

a car moving with an initial velocity of 24m/s comes to a hault in 6s .calulate the distance travelled by the car as it comes to rest
*Saturday, April 25, 2015 by aayushi*

**Physics Capacitance**

Three uncharged capacitors, X, Y, Z, each with capacitance of 12uF each are connected A---------[X]------[Y/Z]-----------B *Y&Z is parallel to each other* A potential difference of 9.0V is applied between points A and B. Explain why when the potential difference of 9.0V is ...
*Saturday, April 25, 2015 by Ariana*

**Physics**

A car drives at a speed of 28m/s along a road parallel to a railroad track. A train traveling at 15m/s sounds a horn that vibrates at 300 Hz. If the train and car are moving toward each other, what frequency of sound is heard by a person in the car? If the train and car are ...
*Saturday, April 25, 2015 by Anonymous *

**PHYSICS answer check**

A group of 4 rail cars with a total mass of 50,000kg moves at 3m/s at a stationary locomotives that has a mass of 10,000kg. What is the speed of the whole train after the cars connect with the locomotive? F=ma 50,000kg*3m/s= 150,000kg m/s 150,000kg m/s divided by 60,000kg a= 2...
*Saturday, April 25, 2015 by MJW*

**PHYSICS**

A corvette ZR1 can brake to a stop from 60mph in 2.6 seconds. If the car has a weight of 3225 pounds, what force (in Newtons) acts on the car? a= (V^2 - V^1)/t a= (0-88ft/sec)/2.6 sec a= -10.316 m/s^2 -10.32N Is this correct?
*Friday, April 24, 2015 by MJW*