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August 29, 2015

Homework Help: Science: Physics

Recent Homework Questions About Physics

physics
A block slides on a rough 45 degree incline .the coefficient of friction the block and incline is µk. what is the ratio of acceleration when the block accelerates down the incline to the acceleration when the block is projected up the incline?
Saturday, December 20, 2014 by awash

physics
A person can jump to a height of 1.5m on surface of earth. Find the velocity with which he jumps.
Saturday, December 20, 2014 by rak!@#$%^&

physics
explain the terms uniform acceleration and average speed.
Saturday, December 20, 2014 by olambs ibrahim

physics
A small sphere of mass m is connected to the end of a cord of length r and rotates in a vertical circle about a fixed point O. The tension force exerted by the cord on the sphere is denoted by T . What is the correct equation for the forces in the radial direction when the ...
Saturday, December 20, 2014 by arianna

Physics
What is the purpose of the resonator stringed instrument
Saturday, December 20, 2014 by danny

physics please help
A hoodlum throws a rock straight down from the roof of a building 109m high. If it takes 2.40s to hit the ground below, with what initial speed was the rock thrown? Please show all work
Saturday, December 20, 2014 by Georgy

Physics please help
TIgers pitcher justin throws a basketball staright upward 29.0m/s. Calculate A) the height to which the ball will rise b) the time it takes to reach the highest point c) the speed with which it will return to the same height which it was thrown d) the speed of the ball 2.50s ...
Saturday, December 20, 2014 by unknown

physics please help
black bart and wyatt earp have a race. wyatt moseys 400m in 58.0s and bart moseys the same distance in 60.0s. by what Distance does wyatt beat bart in this race? Please show all work would greatly appreciate have a test coming up and i don't understand at all how to do it
Friday, December 19, 2014 by unknown

NEED HELP ASAP PHYSICS
A car traveling 16.0m/s crashes into concrete embankment and stops in 0.08s. Calculate: the initial speed in mi/hr the average acceleration of the car during the collision in m/s^2 Please show all work than you
Friday, December 19, 2014 by MARIE

PHYSICS NEED HELP ASAP
A car traveling 16.0m/s crates into concrete embankment and steps in 0.08s. Calculate: the initial speed in mi/hr the average acceleration of the car during the collision in m/s^2 Please show all work than you
Friday, December 19, 2014 by MARIE

physics
How does a “pop bottle” rocket use the principles of motion
Friday, December 19, 2014 by federalaltitude

Physics AIPMT
A stone is dropped under gravity from rest from a height h and it travels a distance 9h/25 in the last second. What is the height H?
Friday, December 19, 2014 by Sharook

physics
The movement of an object or a point mass at a constant speed around a circle that has a fixed radius is called uniform
Thursday, December 18, 2014 by alex

Honors Physics
A canoeist is trying to paddle upstream in a river that has a velocity of 6.1 m/s. If he can paddle his canoe at a velocity of 6.2 m/s, will he make any headway? What will his velocity relative to the shore be?
Thursday, December 18, 2014 by Caroline

physics
If you use a horizontal force of 30.0 N to slide a 12.0 kg wooden crate across a floor at a constant velocity, calculate the acceleration.
Thursday, December 18, 2014 by Anonymous

Physics
starting from rest a 7.5 kg suitcase slides down a 30 degree frictionless incline a distance of 3.1 m upon reaching the bottom it slides an additional 5 m before coming to a stop. a) determine speed of suitcase at bottom of ramp b) determine coefficient of kinetic friction ...
Thursday, December 18, 2014 by Anonymous

Physics
65 kg pole vaulter running at 10.2 m/s vaults over the bar. if height of bar was set at 4.96 m how fast was he moving as he cleared the bar
Thursday, December 18, 2014 by Anonymous

Physics
800 n student is standing in middle of frozen pond stranded 6.4 m from shore only thing he has is physics book which has mass of 3 kg so he throws it at 10 m/s toward one shore how long does it take him to reach opposite shore
Thursday, December 18, 2014 by Anonymous

biology,chemistry,physics
the contact process prepares purest form of sulphuric acid 2so2+o2=2so3 calculate its kp if following concentrations are found at equilibrium so2=0.59,o2=0.05 and so3=0.259
Thursday, December 18, 2014 by Arooj

physics
9th grade physics sketch a picture of the initial total velocity for the projectile when the angle is at 0 degrees, 30 degrees and 60 degrees. Resolve each into vertical and horizontal components. No velocity given
Wednesday, December 17, 2014 by shilpa

Physics
An attack helicopter is equipped with a 20 mm cannon that fires 116 g shells in the forward direction with a muzzle speed of 819 m/s. The fully loaded helicopter has a mass of 4870 kg. A burst of 96.2 shells is fired in a 4.51 s interval. What is the resulting average force on...
Wednesday, December 17, 2014 by Joe

physics
An arrow is shot at an angle 39◦ with the horizontal. It has a velocity of 54 m/s. How high will the arrow go? The acceleration of gravity is 9.8 m/s^2. Answer in units of m
Wednesday, December 17, 2014 by Stephan

Physics
gtrgrt
Wednesday, December 17, 2014 by Kylie

physics
How much work is done on a lawn mower pulled 3.4 m by a force of 54 N at an angle of 10°?
Wednesday, December 17, 2014 by Corey Golden

Physics
A block of mass 8.1 kg is pulled to the right by an applied force of 76.2 N. If the acceleration is 0.84 m/s^2, how much friction must be present?
Wednesday, December 17, 2014 by Breauna

physics
a child is twirling a 0.0120 kg ball on a string in a horizontal circle whose radius is 0.100m. The ball travels once around the circle in 0.500s. Determine the centripetal force acting on the ball
Wednesday, December 17, 2014 by lindsey

physics
Fall time under g is sqrt 2h/g. Can someone give a derivation from the equations of motion please? Thanks.
Wednesday, December 17, 2014 by charlie

physics
6 point masses of mass m each are at the vertices of a regular hexagon of side l.caculate the forces on any of the masses.
Wednesday, December 17, 2014 by daniya

physics
In compressed state, a spring 3.00 meters long hanging from the ceiling has a potential energy of 2.0 joules. If the entire potential energy is used to release a ball of mass 1.2 kilograms vertically downward, then what is the kinetic energy of the ball when it reaches the ...
Wednesday, December 17, 2014 by juan

Physics
What is the coefficient of friction on a 221.9 gram block of wood with 150 grit sandpaper on the bottom being pulled by .392 newtons. NEED HELP IMMEDIATELY!!!!!! Please and thank you
Wednesday, December 17, 2014 by Corey

Physics
Find the component form of ⃗v given a magni- tude of 9 and an angle of θ = 90◦ with positive
Wednesday, December 17, 2014 by Evelin

Science-Physics
A mover is pushing a crate across the floor. He exerts a force of 500 Newtons and pushes the crate a distance of 5 Meters. How much work did the mover do on the crate?
Wednesday, December 17, 2014 by Katie

physics
the second floor of a house is 6m above street level. How much work is required to lift a 300-kg refrigerator to the second-floor level?
Wednesday, December 17, 2014 by Anonymous

Physics
box of books weighs 350 n is shoved across the floor with a force of 500 n directed downward at angle of 37 with horizontal. if muk between box and floor is .5 how long does it take box to move 4 m starting from rest and what is largest value of muk that will allow the box to ...
Wednesday, December 17, 2014 by Anonymous

physics
A steel ball is thrown vertically upward and a ping pong ball is dropped vertically downward. the two balls roll at the same time. which will have a greater acceleration, why?
Wednesday, December 17, 2014 by Anonymous

Physics
a person standing at the edge of a seaside cliff kicks a stone horizontally over the edge with speed of 31 m/s cliff is 51 m above water. how far from base of cliff does stone land and what is speed of stone when it hits water
Wednesday, December 17, 2014 by Anonymous

Physics
You plan to fly a model airplane of mass 0.655 kg that is attached to a horizontal string. The plane will travel in a horizontal circle of radius 5.50 m. (Assume the weight of the plane is balanced by the upward "lift" force of the air on the wings of the plane.) The...
Wednesday, December 17, 2014 by Anonymous

physics
The radius of curvature of a loop-the-loop for a roller coaster is 11.8 m. At the top of the loop (with the car inside the loop), the force that the seat exerts on a passenger of mass m is 0.80mg. Find the speed of the roller coaster at the top of the loop.
Wednesday, December 17, 2014 by Anonymous

Physics
A 2.13 kg mass is suspended from a string which is pulled upward. The mass accelerates upwards with an acceleration of 3.10m/s2. What is the tension in the string?
Tuesday, December 16, 2014 by Jack

physics
A balloon is rising at 3.6 m/s at same time is blown by wind for 5.4 m/s from east. Find the actual velocity and direction of hte balloon.
Tuesday, December 16, 2014 by noona

physics
The frequency and wavelength of a transverse wave on a string are 340 Hz and 0.70 m, respectively. The tension in the string is 110 N. What is the linear density of the string?
Tuesday, December 16, 2014 by Anonymous

Physics
Using light of wavelength 600.0nm in a double slit apparatus we find delta x = 1.0cm. If we use the same apparatus for light of wavelength 450.0 nm, what is the new delta x on the screen? Delta x = L*lambda/d But L and d are not given, so how do I approach this problem?
Tuesday, December 16, 2014 by Neenah

physics
A soccer ball is kicked with an initial horizontal velocity of 16.5 m/s from a 92 meter high cliff. Determine the time it took the ball to reach the ground and how far the ball got from the edge of the cliff.
Tuesday, December 16, 2014 by aj

Physics
1.) A tennis ball (mass = 57 grams) is held directly above a basketball (mass = 624 grams)that is held 4.7 meters off the ground. Both are dropped simultaneously. Assuming an elastic collision, how high above the ground does the tennis ball reach after bouncing? (Note that the...
Tuesday, December 16, 2014 by Please Help

Physics
An airliner lands with a speed of 48.5 m/s. Each wheel of the plane has a radius of 1.25 m and a moment of inertia of 110 kg · m2. At touchdown, the wheels begin to spin under the action of friction. Each wheel supports a weight of 1.40 ✕ 104 N, and the wheels ...
Tuesday, December 16, 2014 by Elsie

physics
an object is dropped from a vertical cliff. How long does it take to reach 85 km/h?
Tuesday, December 16, 2014 by Anonymous

Physics I
I'm not sure how to address any of these. I"ve attempted them but each time I do, I've gotten different answers. I'm not even sure where to begin. 1. The Duke’s efforts to conquer the Count are starting to really falter. He has been forced back away from ...
Tuesday, December 16, 2014 by Eva

Physics
The radius of curvature of a loop-the-loop for a roller coaster is 11.8 m. At the top of the loop (with the car inside the loop), the force that the seat exerts on a passenger of mass m is 0.80mg. Find the speed of the roller coaster at the top of the loop. 1 m/s
Tuesday, December 16, 2014 by Anonymous

Physics
You plan to fly a model airplane of mass 0.655 kg that is attached to a horizontal string. The plane will travel in a horizontal circle of radius 5.50 m. (Assume the weight of the plane is balanced by the upward "lift" force of the air on the wings of the plane.) The...
Tuesday, December 16, 2014 by Anonymous

physics
A 200 gram copper calorimeter contains 400 grams of water at 25 C. A metal specimen weighing 250 grams is heated to a certain temperature and the plunged into the calorimeter The final temperature of the mixture is 42C. If then specific heat of the metal specimen is 0.09 cal/(...
Tuesday, December 16, 2014 by wendell ryan

Physics
The radius of curvature of a loop-the-loop for a roller coaster is 11.8 m. At the top of the loop (with the car inside the loop), the force that the seat exerts on a passenger of mass m is 0.80mg. Find the speed of the roller coaster at the top of the loop. m/s
Tuesday, December 16, 2014 by Anonymous

physics
Tarzan tries to cross a river by swinging from one bank to the other on a vine that is 12.2 m long. His speed at the bottom of the swing is 8.6 m/s. Tarzan does not know that the vine has a breaking strength of 1.0 ✕ 103 N. What is the largest mass that Tarzan can have ...
Tuesday, December 16, 2014 by Anonymous

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, ...
Tuesday, December 16, 2014 by Anonymous

physics
. A proton is released from rest at point A in a uniform electric field that has a magnitude of . The proton undergoes a displacement to point B in the direction of . Calculate the speed of the proton after completing the displacement.
Tuesday, December 16, 2014 by salem

Physics
I don't completely understand what this question is asking: Three people are standing on a horizontally rotating platform in an amusement park. One person is almost at the edge, the second one is (3/5)R from the center, and the third is (1/2)R from the center. Compare ...
Monday, December 15, 2014 by Todd

physics
A person sitting in a chair (combined mass 80kg) is attached to a 6m long cable. The person moves in a horizontal circle. The cables angle is 62 degrees below the horizontal. What is the persons speed? Note: the radius of the circle is not 6m. I really just need and equation ...
Monday, December 15, 2014 by Todd

physics
Calculate the maximum deceleration of a car that is heading down a 14.5° slope (one that makes an angle of 14.5° with the horizontal) under the following road conditions. You may assume that the weight of the car is evenly distributed on all four tires and that the ...
Monday, December 15, 2014 by mathew

physics
A 75 kg bobsled is pushed along a horizontal surface by two athletes. After the bobsled is pushed a distance of 4.5 m starting from an initial speed of 1.2 m/s, its speed is 6.0 m/s. What is the change in kinetic energy? Find the magnitude of the net force on the bobsled.
Monday, December 15, 2014 by bill

physics
A student wearing frictionless in-line skates on a horizontal surface is pushed, from rest, by a friend with a constant force of 45 N. How far must the student be pushed, starting from rest, so that her final kinetic energy is 352 J?
Monday, December 15, 2014 by bill

physics
How much work is required to accelerate a 0.145 kg baseball from rest, to a speed of 38.7 m/s?
Monday, December 15, 2014 by bill

Physics
In an electricity experiment, a 0.900g plastic ball is suspended on a 50.0cm long string and given an electric charge. A charged rod brought near the ball exerts a horizontal electrical force F⃗ elec on it, causing the ball to swing out to a 23.0∘ angle and remain ...
Monday, December 15, 2014 by Dan

physics
Calculate the half-life of a radioactive substance that decays by a factor of 3 in concentration every 1 million years
Monday, December 15, 2014 by kathy

physics
A dragster starts from rest and accelerates down a track. Each tire has a radius of 0.320 m and rolls without slipping. At a distance of 382 m, the angular speed of the wheels is 255 rad/s. Determine (a) the linear speed of the dragster and (b) the magnitude of the angular ...
Monday, December 15, 2014 by megann

physics
A full shopping cart requires a force of 88.0 Newtons to move across a horizontal floor at a constant velocity. If the cart has a mass of 32.1 kg, what is the coefficient of kinetic friction between the cart and the floor?
Monday, December 15, 2014 by bruh

Physics
Instructions: Read the following paragraph carefully. Then use what you know about momentum, work, and energy to answer the following questions. Be sure to show your work. You are a traffic accident investigator. You have arrived at the scene of an accident. Two cars of equal ...
Monday, December 15, 2014 by Anonymous

Physics
Instructions: Read the following paragraph carefully. Then use what you know about momentum, work, and energy to answer the following questions. Be sure to show your work. You are a traffic accident investigator. You have arrived at the scene of an accident. Two cars of equal ...
Monday, December 15, 2014 by Annet

physics
A skier starts from rest and slides down a 20° incline 100 meters long. if the coefficient of friction is 0.09, how much heat is dissipated into the environment as the skier descends?
Monday, December 15, 2014 by Kaya Allen

Physics
A ball is thrown upwards with an initial velocity of 16 m/s. What is the velocity of the ball 1.5 s later? After the ball leaves the hand of the thrower, what is the value of acceleration acting on the ball as it is rising upwards? 9.8x1.5 = 14.7. 16-14.7=1.3 m/s after 1.5s. ...
Monday, December 15, 2014 by Jim

physics
a jogger does 2.5 *10^5 of work during an exercise routine. her internal energy decreases by 6.8*x10^5. how much heat did she absorb or give off?
Monday, December 15, 2014 by innocent

Physics AP
So there are two blocks that are connected over a light frictionless pulley. Block A has a mass of 2 kg on a frictionless surface while block b has a mass of 1 kg that hangs freely. It asks for speed, change in speed, and tension. I know that tension can be 2m1m2/m1m2 times g...
Monday, December 15, 2014 by Jelly

physics
radius R of the orbit of a geosynchronous satellite that circles the earth. (Note that R is measured from the center of the earth, not the surface.) You may use the following constants: The universal gravitational constant G is 6.67×10−11N⋅m2/kg2. The mass of...
Sunday, December 14, 2014 by cara

Physics
A 283 g air track glider moving at 0.69 m/s on a 2.4 m long air track collides elastically with a 467 g glider at rest in the middle of the horizontal track. The end of the track over which the struck glider moves is not frictionless, and the glider moves with a coefficient of...
Sunday, December 14, 2014 by David

physics
What happens to the diffraction pattern when you have a small wavelength and large slit width in single slit interference? Say you have a light of 700nm shining through a diffraction grating with the separation of slits being 450nm. What pattern would you see? The answer is ...
Sunday, December 14, 2014 by Jamie

physics
There are 45,000 calories in one ounce of pasta, how many ounces do i have to eat to get from ground floor to the 3rd floor (18.2 m)? my weight is 58kg
Sunday, December 14, 2014 by Anonymous

physics
A car is moving at 53 miles per hour. The kinetic energy of that car is 5 × 105 J. How much energy does the same car have when it moves at 102 miles per hour? Answer in units of J HELP!!!! I've tried doing (5*10 J)* (102/53)^2 and I keep on getting it wrong PLEASE ...
Sunday, December 14, 2014 by Edgar

physics
A radar antenna is tracking a satellite orbiting the earth. At a certain time, the radar screen shows the satellite to be 181 km away. The radar antenna is pointing upward at an angle of 66.2 ° above the ground. Find (a) the x and (b) the y components (in km) of the ...
Sunday, December 14, 2014 by need help

physics
In a football game a kicker attempts a field goal. The ball remains in contact with the kicker's foot for 0.0442 s, during which time it experiences an acceleration of 231 m/s2. The ball is launched at an angle of 55.0° above the ground. Determine the (a) horizontal ...
Sunday, December 14, 2014 by need help

physics
A rope attached to a truck pulls a 180-kg motorcycle at 9.0 m/s. The rope exerts a 400-N force on the motorcycle at an angle of 15∘ above the horizontal. What is the work that the rope does in pulling the motorcycle 300 m? Express your answer with the appropriate units.
Sunday, December 14, 2014 by Myah

physics
A 5 kg object moving with a speed of 6.6 m/s collides with an 18 kg object moving with a velocity of 8.4 m/s in a direction 19 degrees from the initial direction of the motion of the 5 kg object. What is the speed of the two objects after collision if they remain stuck ...
Sunday, December 14, 2014 by hayden

physics
A block at rest. The coefficients of static and kinetic friction are .75(Static) and .64(Kinetic). The acceleration of gravity is 9.8m/s^2 and the mass is 46kg. I've solved for the frictional force which is, 252.0841609N. Though what is the largest angle which the incline ...
Sunday, December 14, 2014 by allan

physics
I need some help with determining the equation for this problem. "The block of mass m is released from rest on the frictionless incline. After sliding a certain distance, it compresses a spring and comes to rest at a distance of y beneath its original position. How much ...
Sunday, December 14, 2014 by Maddy

physics
In the drawing, the weight of the block on the table is 428. N and that of the hanging block is 195. N. Ignore friction, the mass of the rope, and the mass of the pulley. Find the acceleration of the two block system in m/s2.
Sunday, December 14, 2014 by Jill

physics
A cup of coffee is sitting on a table in an airplane that is flying horizontally. The coefficient of static friction between the cup and the table is 0.258. Suddenly, the plane accelerates horizontally. What is the maximum acceleration (in m/s2) that the plane can have without...
Sunday, December 14, 2014 by Jill

physics
A student is skateboarding down a ramp that is 6.52 m long and inclined at 19.8 degrees with respect to the horizontal. The initial speed of the skateboarder at the top of the ramp 2.24 m/s. Neglect friction and find the speed at the bottom of the ramp in m/s.
Sunday, December 14, 2014 by Jill

Physics
A body moving with uniform acceleration covers 64.4 m in 7s and 110 m in 10s. Find its initial velocity and acceleration. Okay, I know how to solve this, however, i'm not quite sure which equation i'm supposed to use. Am I going to need 2 equations to solve this?
Sunday, December 14, 2014 by Mellissa

Physics
An object is thrown upwards from a height of 50.0m at an initial speed of 19.6m/s. Determine how long will it take for the object to reach the ground.
Sunday, December 14, 2014 by cams

PHYSICS
FIND THE PRESSURE EXERTED ON A 6FTX10FT WALL BY THE ATMOSPHERE, IF ATMOSPHERE PRESSURE IS 14.7 PSI.
Sunday, December 14, 2014 by SIVA RAM

physics
Calculate the acceleration of a sled that is heading down a 50° slope (one that makes an angle of 50° with the horizontal). The coefficient of kinetic friction on ice is μk = 0.100. (Take the x direction to be parallel to and down the slope and the y direction to ...
Sunday, December 14, 2014 by mathew

Physics
A projectile is shot vertically upward with a given initial velocity. It reaches a maximum height of 100 m. If, on a second shot, the initial velocity is doubled then the projectile will reach a maximum height of ____________?
Saturday, December 13, 2014 by John

Physics
A bowling ball slows down at rate of .12 m/s^2. 5 seconds after it starts down the bowling alley its speed is 15 m/s. What was its initial speed?
Saturday, December 13, 2014 by Rachel

physics
Calculate the mass of the air in a 5 m ✕ 3 m ✕ 2.5 m room, assuming that it is at 1 atm and 19°C.
Saturday, December 13, 2014 by Anonymous

Physics
An archer needs to hit a bull’s eye on a target at eye level 60.0 ft away. If the archer fires the arrow from eye level with a speed of 47.0 ft/s at an angle of 25 degree above the horizontal, will the arrow hit the target?
Saturday, December 13, 2014 by J_nin

physics
In state-of-the-art vacuum systems, pressures as low as 1.00 10-9 Pa are being attained. Calculate the number of molecules in a 1.80-m3 vessel at this pressure and a temperature of 31.0°C.
Saturday, December 13, 2014 by shawn

physics
The pressure gauge on a tank registers the gauge pressure, which is the difference between the interior pressure and exterior pressure. When the tank is full of oxygen (O2), it contains 10.0 kg of the gas at a gauge pressure of 43.0 atm. Determine the mass of oxygen that has ...
Saturday, December 13, 2014 by shawn

physics
Gas is contained in a 6.00-L vessel at a temperature of 15.0°C and a pressure of 6.00 atm. (a) Determine the number of moles of gas in the vessel. (b) How many molecules are in the vessel?
Saturday, December 13, 2014 by Meagan

physics
A rigid tank contains 1.80 moles of an ideal gas. Determine the number of moles of gas that must be withdrawn from the tank to lower the pressure of the gas from 21.6 atm to 5.80 atm. Assume the volume of the tank and the temperature of the gas remain constant during this ...
Saturday, December 13, 2014 by Meagan

physics
Gas is confined in a tank at a pressure of 12.7 atm and a temperature of 22.0°C. If two-thirds of the gas is withdrawn and the temperature is raised to 79.0°C, what is the pressure of the gas remaining in the tank?
Saturday, December 13, 2014 by Meagan

physics
A sample of lead has a mass of 69.00 kg and a density of 1.130 104 kg/m3 at 0°C. (Assume the average linear expansion coefficient for lead is 2.900 10-5(°C−1).) (a) What is the density of lead at 80.00°C? (Give your answer to four significant figures.) (b) ...
Saturday, December 13, 2014 by Meagan

physics
A hollow aluminum cylinder 22.5 cm deep has an internal capacity of 2.000 L at 16.0°C. It is completely filled with turpentine at 16.0°C. The turpentine and the aluminum cylinder are then slowly warmed together to 70.0°C. (The average linear expansion coefficient ...
Saturday, December 13, 2014 by Lior

physics
The active element of a certain laser is made of a glass rod 29.0 cm long and 1.20 cm in diameter. Assume the average coefficient of linear expansion of the glass is equal to 9.00 10-6 (°C)-1. The temperature of the rod increases by 70.0°C. (a) What is the increase in ...
Saturday, December 13, 2014 by Lior

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