Friday
December 9, 2016

Homework Help: Science: Physics

Recent Homework Questions About Physics

Physics
1. A 10-kg object is dropped from rest. After falling a distance of 50 m, it has a speed of 26 m/s. a. Write the expression for the change in mechanical energy caused by the dissipative (air) resistive force on the object during this descent. b. Calculate the energy.
Tuesday, October 25, 2016 by Aprill

PHYSICS
What is the magnitude of the instantaneous velocity (speed) of a freely falling object 13 s after it is released from a position of rest? Consider the acceleration of gravity to be 10 m/s2 .
Tuesday, October 25, 2016 by MEGAN

Physics
Several forces are applied to an object. If the object 40 m along the horizontal, and if one of the forces is a constant 5.0 N in the opposite direction, then what is the worst done on the object by that force?
Tuesday, October 25, 2016 by Mary

Physics
Judy, by chance, spots a potted plant falling outside the window at 1.6 m/s. Further down the same building, Judy’s boyfriend clocks the pot at 80 m/s. How far apart are the friends? The acceleration of gravity is 9.8 m/s^2. Answer in units of m. Plz help
Tuesday, October 25, 2016 by Jazz

physics
An atomic nucleus at rest decays radioactively into an alpha particle and a nucleus smaller than the original. What will be the speed of this recoiling nucleus if the speed of the alpha particle is 1.20E+05 m/s? Assume the recoiling nucleus has a mass 56 times as great as that...
Tuesday, October 25, 2016 by kassy

physics
A 46 g bullet strikes and becomes embedded in a 1.27 kg block of wood placed on a horizontal surface just in front of the gun. If the coefficient of kinetic friction between the block and the surface is 0.28, and the impact drives the block a distance of 16.0 m before it ...
Tuesday, October 25, 2016 by kassy

physics
A horizontal circular platform (m = 122.1 kg, r = 3.43m) rotates about a frictionless vertical axle. A student (m = 82.3kg) walks slowly from the rim of the platform toward the center. The angular velocity, omega, of the system is 2.9 rad/s when the student is at the rim. Find...
Tuesday, October 25, 2016 by taylor

physics
What is the gravitational potential energy of a ball with a weight of 72 N when it is sitting on a shelf 1.4 m above the floor?
Tuesday, October 25, 2016 by Sue

physics
3 kg block (block A) is released from rest at the top of a 20 m long frictionless ramp that is 5 m high. At the same time, an identical block (block B) is released next to the ramp so that it drops straight down the same 5 m. Find the values for each of the following for the ...
Tuesday, October 25, 2016 by Katelyn

physics
A 5 kg toy car with a speed of 6 m/s collides head-on with a stationary 1 kg car. After the collision, the cars are locked together with a speed of 5.00 m/s. How much kinetic energy is lost in the collision?
Tuesday, October 25, 2016 by Beth

Physics
A 23-kg child is sliding on an icy surface toward her mother at 3.0 m/s. Her 70-kg mother starts toward her at 2.0 m/s, intending to catch her. What percentage of the original kinetic energy is convertible? I calculated the convertible kinetic energy as Kconv=1/2*(m1)(m2)/(m1+...
Tuesday, October 25, 2016 by Tori

Physics
A 1300 kg car traveling at a steady speed of 15 m/s initially due northwest round a corner so that after 10s, it is traveling due northeast. What is the magnitude and direction of the net force that must be acting on the car at the instant it is traveling due north?
Tuesday, October 25, 2016 by Josh

Science/Physics
The speed of light in a certain medium is 61.2% of the speed of light in vacuum. What is the index of refraction of the medium?
Tuesday, October 25, 2016 by Maykayla

AP Physics 2
Identical point charges of +3.3 µC are fixed to three of the four corners of a square. What is the magnitude |q| of the negative point charge that must be fixed to the fourth corner, so that the charge at the diagonally opposite corner experiences a net force of zero?
Tuesday, October 25, 2016 by Brandon

Physics
A rocket leaves the launch pad heading straight up with a constant acceleration of 60 m/s^2 \. its initial stage booster runs out in 25 seconds. How high is the rocket?
Tuesday, October 25, 2016 by Caden

physics projectile
A ball is thrown with an initial velocity of 20mls at an angle of 30 to the horizontal calculate time of flight maximum height the horizontal range of the ball how do I know If you have done it
Tuesday, October 25, 2016 by onyebuchi ogor

Physics Help!
A hockey puck moving at 0.4600 m/s collides with another puck that was at rest. The pucks have equal mass. The first puck is deflected 37.00° to the right and moves off at 0.3700 m/s. Find the speed and direction of the second puck after the collision.
Tuesday, October 25, 2016 by Helena

Physics
The length breadth and the height of the brick is 25cm,7cm and 4cm respectively.Finf the pressure exerted by the Buick when it is kept 1.horizontally, 2.Vertically on a muddy floor and compare.
Monday, October 24, 2016 by Meenakshi

Physics
The angle of a sector of a circle is 75 If the radius of this circle is increasing at the rate of 0.3cm/s find the rate of increase of the area when the radius is 6cm
Monday, October 24, 2016 by Favour

Physics
A 1.96 kg toy train rolls around a circular horizontal track. If the train has an angular acceleration of -1.95 rads/s2 and is released with an angular speed of 33.0 rpm, what time is required for the train to come to a complete stop?
Monday, October 24, 2016 by Anonymous

Physics
The 10 kg mass is released from rest at a height of 1m above the floor. If the co-efficient of kinetic friction between the 5 kg mass and the table is 0.28, what will be the speed of the 10 kg mass just before it hits the floor? Please show the equation and then plug the ...
Monday, October 24, 2016 by Anonymous

physics
A 7.4kg block starts 1.2m above the ground, at the top of a frictionless ramp. At the bottom of the ramp is a flat stretch of rough (μk = 0.15) ground 3.0m long. After sliding 3.0m, the ground becomes frictionless, and the block hits a spring (k = 1.6kN/m). a. Calculate ...
Monday, October 24, 2016 by April

Physics
Jane swings on a 30m long vine initially inclined at an angle of 37o from the (downward) vertical. What is her speed at the bottom of her swing if a) she starts from rest? b) she pushes off with an initial speed of 4 m/s? Help please. Show the equation and then plug in the ...
Monday, October 24, 2016 by Anonymous

Physics
A pitcher hurls a 0.25kg ball around a vertical circular path of radius 0.6 m, applying a tangential force of 30N, before releasing it at the bottom of the circle (underhand pitch). If the speed of the ball at the top of the circle was been 15 m/s, what will be the speed just ...
Monday, October 24, 2016 by Anonymous

Math
In physics, one learns that the height of an object thrown upward from an initial height of h0 feet with an initial velocity of v0 (in feet per second) is given by the formula h(t)=−16t^2+v0t+h0 feet where t is the amount of time in seconds after the ball was thrown. ...
Monday, October 24, 2016 by Anonymous

Physics
A force of -9000N is used to stop a 1500 kg car traveling at 20m/s. What braking distance is needed to bring the car to a halt?
Monday, October 24, 2016 by Melissa

physics projectile
A ball is thrown with an initial velocity of 20mls at an angle of 30 to the horizontal calculate time of flight maximum height the horizontal range of the ball how do I know If you have done it
Monday, October 24, 2016 by onyebuchi ogor

physics projectiles
A ball is thrown with an initial velocity of 20mls at an angle of 30 to the horizontal calculate time of flight maximum height the horizontal range of the ball (2)A bullet is fired with a velocity of 50meter per seconds at an angle 0 to the horizontal (a)what is the value of 0...
Monday, October 24, 2016 by onyebuchi ogor

physics projectiles
A ball is thrown with an initial velocity of 20mls at an angle of 30 to the horizontal calculate time of flight maximum height the horizontal range of the ball
Monday, October 24, 2016 by onyebuchi ogor

Physics
A 1500kg car traveling at a steady speed of 20 m/s initially due northwest round a corner so that after 10s, it is traveling due northeast. What is the magnitude and direction of the net force that must be acting on the car at the instant it is traveling due north?
Monday, October 24, 2016 by Micheal

Physics
The objects listed below are placed at the top of a ramp, and roll down to the bottom without slipping. Assuming that there is no air resistance, rank them in order from fastest average rolling speed to slowest. Basketball Bowling Ball Penny Wedding Ring
Monday, October 24, 2016 by Morgan

Physics
A sphere of radius 2.84 cm and a cylinder of radius 8.97 cm are rolling without slipping along the same floor. The two objects have the same mass. If they are to have the same total kinetic energy, what should the ratio of the sphere\'s angular speed to the cylinder\'s...
Monday, October 24, 2016 by Morgan

Physics
A propeller is modeled as five identical uniform rods extending radially from its axis. The length and mass of each rod are 0.721 m and 2.55 kg, respectively. When the propellor rotates at 561 rpm (revolutions per minute), what is its rotational kinetic energy?
Monday, October 24, 2016 by Morgan

Physics
A baseball pitcher throws the ball in a motion where there is rotation of the forearm about the elbow joint as well as other movements. If the linear velocity of the ball relative to the elbow joint is 19.7 m / s at a distance of 0.470 m from the joint and the moment of ...
Monday, October 24, 2016 by Morgan

physics
A mass of 1kg is placed at 1m,2m,0.Another mere of 2kg is placed at 3m,4m,0.Find moment of inertia of both the ladder about z-axis
Monday, October 24, 2016 by Gauravi

Physics
How much heat must be added to 1-kg of 0 degrees Celsius water to turn it into water at 50 degrees Celsius? If the water had been ice at 0 degrees Celsius, would that increase, decrease, or not change the amount of energy required?
Monday, October 24, 2016 by Teresa

physics
two force 12N and 24N,90degree that find two force
Monday, October 24, 2016 by TESFAYE

Physics
A 3.65 kg steel block is spun around a motor at 44.0 rpm. The angular acceleration of the block is -1.3 rads/s2 and it takes 3.54 s for the block to come to a complete stop. What is the angular displacement while the block slows to a stop?
Monday, October 24, 2016 by Tim

Physics
A 59.6 g box is left 17.5 cm from the centre of a merry-go-round. If the box has coefficients of friction of μs = 0.790 and μk = 0.550 with the merry-go-round, what is the maximum speed of the merry-go-round without having the box slide off of the merry-go-round?
Monday, October 24, 2016 by Lana

physics
A highway is being constructed to accommodate traffic for speeds of 22.8 m/s. If the angle of the bank is 6.28° and there is no friction force, what is the highway's curve radius?
Monday, October 24, 2016 by abdul

physics
A ball of mass 2kg travelling in a straight line at 4ms^-1 is acted on by a force of 3N acting in the direction of motion for 5 seconds. What is the speed of the ball after 5 seconds? vf=vi+at but a=force/mass a = 3÷2= 1.5 vf=4+1.5×5= vf=4+7.5 vf=11.5m/s^-1 Is ...
Monday, October 24, 2016 by Saphina AlMatary

Physics
A ball of mass 2kg travelling in a straight line at 4ms^-1 is acted on by a force of 3N acting in the direction of motion for 5 seconds. What is the speed of the ball after 5 seconds?
Monday, October 24, 2016 by Saphina AlMatary

Physics
An object of mass 12kg is pushed 34m up a frictionless slope that is at an angle of 56^o to the horizon. Determine both (a) the work on the object and (b) its change on gravitational potential energy.
Monday, October 24, 2016 by Saphina AlMatary

Physics
An orange of mass 40g falls freely from a tree to the ground through a distance of 2.5m. Calculate the velocity just before it hits the ground. Velocity = speed/time I have no speed or time so what do I do.
Monday, October 24, 2016 by Komori

physics
Helium gas occupies a volume of 0.04 m 3 at a pressure of 2 x 10 5 Pa (Nm -2 ) and temperature of 300 K. Calculate (i) the mass of the helium. (ii) the r.m.s. speed of its molecules. (iii) the r.m.s. speed at 432 K when the gas is heated at constant pressure to this ...
Monday, October 24, 2016 by ruth

physics
You pick up a 3.2 kg can of paint from the ground and lift it to a height of 1.4 m . Part A How much work do you do on the can of paint? Express your answer to two significant figures and include the appropriate units. Part B You hold the can stationary for half a minute, ...
Monday, October 24, 2016 by ...

physics
You raise a bucket of water from the bottom of a well that is 12 m deep. The mass of the bucket and the water is 5.00 kg, and it takes 15 s to raise the bucket to the top of the well. Part A How much power is required?
Sunday, October 23, 2016 by ...

physics
A stone is moved round a horizontal circle with a 20 cm long string tied to it. if centrepetal acceleration is 9.8 m/s2, then its angular velocity
Sunday, October 23, 2016 by charu

Physics
A 83.0-kg person, hanging from a rope, is being pulled away from a burning building by a firefighter, as shown in the figure below.
Sunday, October 23, 2016 by Mikayla

Physics
A box of mass m = 59.0 kg (initially at rest) is pushed a distance d = 84.0 m across a rough warehouse floor by an applied force of FA = 204 N directed at an angle of 30.0° below the horizontal. The coefficient of kinetic friction between the floor and the box is 0.100. ...
Sunday, October 23, 2016 by Daisy

Physics
A ball is on the end of a rope that is 1.75 m in length. The ball and rope are attached to a pole and the entire apparatus, including the pole, rotates about the pole's symmetry axis. The rope makes an angle of 78.0° with respect to the vertical. What is the tangential...
Sunday, October 23, 2016 by Ray

physics
A car starts from rest and accelerates for 8.7 s with an acceleration of 4.4 m/s 2 . How far does it travel? Answer in units of m.
Sunday, October 23, 2016 by Jess

physics
During strenuous exercise, it is possible to exert forces to the joints easily ten times greater than the weight being supported. What is the maximum force of friction under such conditions? The frictional forces in joints are relatively small in all circumstances except when ...
Sunday, October 23, 2016 by tia

Physics
Your daredevil friends attach a rope to a 140kg sled that rests on a frictionless icy surface. The rope extends horizontaly to a smooth dead tree trunk lying at the edge of a cliff. Another person attaches a 30kg rock at the end of the rope after it passes over the tree trunk ...
Sunday, October 23, 2016 by Hang

physics
A 64.8 g drink is left on a turntable causing it to turn with an angular speed of 8.50 rad/s. If the drink has coefficients of friction of μs = 0.890 and μk = 0.500 with the turntable, what is the furthest distance that the drink could have been placed from the ...
Sunday, October 23, 2016 by kate

physics
A race car track has been constructed with the a bank angle of 32.7° so there is no friction force. The race car track has a curve radius of 394 m. What speeds, for the race cars, has the track been designed to accommodate?
Sunday, October 23, 2016 by marina

Physics
The mass of a spacecraft is about 480 kg. An engine designed to increase the speed of the spacecraft while in outer space provides 0.09 N thrust at maximum power. By how much does the engine cause the craft's speed to change in 1 week of running at maximum power? Describe ...
Sunday, October 23, 2016 by Anna

Physics
An object of mass m1 is placed on an inclined plane (angle theta above the horizontal) is connected by a string going over a pulley to a hanging object of mass m2. Determine the acceleration of the system if there is no friction between object 1 and the surface of the inclined...
Sunday, October 23, 2016 by Anna

Physics
You push a 1kg block against a spring with spring constant k = 100 Nmon a horizontal table top. The spring is compressed to 0.2m away from its relaxed length, and then the block is released. If the horizontal table top has a coefficient of kinetic friction of 0.2, how much ...
Sunday, October 23, 2016 by Kevin

Physics
Ball 1 initially travels with a velocity of u m/s.Ball 2 is stationery and has a mass of 0.2kg and this collision lasts for 0.1 s.Afterwards both balls move in the direction of ball 1's initial velocity. Each ball has a different final velocity. During the collision a ...
Sunday, October 23, 2016 by Wasim

Physics
A 0.630 kg wooden block is spun around on a wooden table. The wooden block is being spun around on a 2.00 m long massless wire. The wooden block has air being pushed out behind it causing a thrust force of 3.30 N. The air is being pushed out at 70.0° from the radial line ...
Sunday, October 23, 2016 by Fred

Physics
You toss a tennis ball straight upward. At the moment it leaves your hand it is at a height of 1.3 m above the ground, and it is moving at a speed of 7.4 m/s. (a) How much time does it take for the tennis ball to reach its maximum height? (b) What is the maximum height above ...
Sunday, October 23, 2016 by Mary

Physics
Particle A makes a perfectly elastic collision with another particle B at rest they fly apart in opposite direction with equal speeds the ratio of their masses mA/mB is?
Sunday, October 23, 2016 by Mritunjay Pandey

Physics
Weight of an object on the surface is 100N . What will we it's weight a planet whose mass 10times that of earth and radius is 3 times as that of earth??
Sunday, October 23, 2016 by Rani solanki

Physics
A 350-kg disk-shaped non-rotating satellite gets hit by a 5-g piece of space debris moving at 1.5 km/s. If the debris buries itself near the satellite’s rim, how rapidly will the satellite rotate after the hit?
Sunday, October 23, 2016 by Josh

Physics
A football quarterback shows off his skill by throwing a pass 45.90 m downfield and into a bucket. The quarterback consistently launches the ball at 40.00 ∘ above horizontal, and the bucket is placed at the same level from which the ball is thrown. What initial speed is ...
Saturday, October 22, 2016 by Lily

physics
Calculate the mass of moon if free fall acceleration near it surface is know be 1.62 m/s^2 ( radius of moon is 1738 Km )
Saturday, October 22, 2016 by Anonymous

Physics
If vector A×vector B=0,does it necessary follow that A=0 or B=0? Explain.
Saturday, October 22, 2016 by Amrit

physics
If a 5kg object experiences a 10 N force for a duration of 0.10 second then what is the momentum change of the object.
Saturday, October 22, 2016 by Manilyn

physics
The water tank is 8 m above the tap. What pressure forces the water out from the tap?
Saturday, October 22, 2016 by Manilyn

physics
The pressure of water on the ground floor is 40,000 Pascal, and at the first floor is 10,000 pascal. Find the height of the first floor.
Saturday, October 22, 2016 by Manilyn

physics
If the systolic blood pressure is 120mmHg, what is the pressure in lb/in^2 and in pascals?
Saturday, October 22, 2016 by Manilyn

physics
What is the pressure of the water in pascals at the bottom og a lake which is 5 meters deep?
Saturday, October 22, 2016 by Manilyn

physics
The center of a 1.00km diameter spherical pocket of oil is 1.00kkm beneath the Earth's surface. Estimate by what percentage g directly above the pocket of oil would differ from the expected value of for a uniform Earth? Assume the density of oil is 8.0*10^2kg/m^3. Δg/...
Saturday, October 22, 2016 by katie bornia

physics
Question 6) Oil and gas exploration companies find new underground deposits by measuring (with incredible precision) the value of g at the Earth's surface. EXTRA INFO GIVEN: The challenge: F=Gm1m2/r^2 ONLY works for two cases: point masses, or if one of the masses has ...
Saturday, October 22, 2016 by katie bornia

Physics
An astronaut with mass M floating at rest in the International Space Station catches a spinning frisbee that someone has thrown directly towards his or her center of mass. The frisbee has a mass m, a radius r, a moment of inertia of ⅔ mr2, and had a speed vo and was ...
Saturday, October 22, 2016 by Juan L

physics numerical
A 15 g bullet is fired from a gun of mass 2kg with a speed of look m/s . Find the recoil velocity of the gun.
Saturday, October 22, 2016 by Anonymous

Repost(Physics)
A vehicle moves in a straight line with an acceleration of 2 km/h^2. By how much does the speed change each second? Answer in units of km/h. Plz help?
Saturday, October 22, 2016 by Jazz

Physics
A vehicle moves in a straight line with an acceleration of 2 km/h^2. By how much does the speed change each second? Answer in units of km/h. Plz help?
Saturday, October 22, 2016 by Jazz

Physics
A 1.11 kg toy train rolls around a circular horizontal track. If the train has an angular acceleration of -2.2 rads/s2 and is released with an angular speed of 17.0 rpm, what time is required for the train to come to a complete stop?
Saturday, October 22, 2016 by Tom

Physics
A 51.6 g box is left 17.8 cm from the centre of a merry-go-round. If the box has coefficients of friction of μs = 0.790 and μk = 0.480 with the merry-go-round, what is the maximum speed of the merry-go-round without having the box slide off of the merry-go-round?
Saturday, October 22, 2016 by Tom

Math Physics Torque Equilibrium
A uniform meterstick pivoted at its center has a 100 g mass suspended at the 21.0 cm position. At what position should a 95.0 g mass be suspended to put the system in equilibrium? What mass would have to be suspended at the 80.0 cm position for the system to be in equilibrium?
Saturday, October 22, 2016 by Brandon

Physics
in the laboratory frame, a photon of energy 8.0 x 10^3 eV and a free electron of energy 2.0 x 10^3 eV (consider what is meant by 'energy' here; is it kinetic energy? total energy? can it be total energy?) are moving directly towards each other and collide head on. a) ...
Saturday, October 22, 2016 by deniz

Physics
Is it possible that resultant of two vectors e smaller than the smaller of the two vectors?
Saturday, October 22, 2016 by Sonika

Physics
A 500-kg disk-shaped nonrotating satellite gets hit by a 5-g piece of space debris moving at 1 km/s. If the debris buries itself near the satellite’s rim, how rapidly will the satellite rotate after the hit?
Saturday, October 22, 2016 by Megan

Physics
I've been stuck on this questions for 2 days A 7.2-kg bowling ball traveling at a speed of 3.5 m/s collides with a 1.2-kg bowling pin at rest. After the collision, the pin moves with a speed of 3.0 m/s at an angle of 60° with respect to the original direction of motion...
Saturday, October 22, 2016 by Lana

physics
I have put a 100 gram weight ball in a plastic bottle and weight of this bottle is 20 gram .Now I shake this bottle in horizontal direction towards 5 centimeter back and forth with the applying force of 1 newton .So what will be the kinetic energy of this ball?
Saturday, October 22, 2016 by vikram

Physics
Can you find a vector quantity that has a magnitude of zero but components that are different from zero? Explain.
Saturday, October 22, 2016 by Amrit

Physics
Can you find two vectors with different lengths that have a vector sum of zero? What length restrictions are required for three vectors to have a vector sum zero? Explain.
Saturday, October 22, 2016 by Amrit

Physics
Can you find two vectors with different lengths that have a vector sum of zero? What length restrictions are required for three vectors to have a vector sum zero? Explain.
Friday, October 21, 2016 by Amrit

Physics
Two vectors A and B have magnitude A=3 and B=3,their vector product is A×B=2i-5k what is the angle between vector A and B?
Friday, October 21, 2016 by Amrit

Physics
Two bodies with equal momentum have KE in the ratio 5:4. What will be the ratio of their masses be?
Friday, October 21, 2016 by Prism

Physics
What is the order of drift velocity of electron during the flow of current through the metal?
Friday, October 21, 2016 by Prism

PHYSICS: PLEASE HELP A.S.A.P HMK DUE AT MIDNIGHT T
During a storm, a car traveling on a level horizontal road comes upon a bridge that has washed out. The driver must get to the other side, so he decides to try leaping the river with his car. The side of the road the car is on is 21.9 m above the river, while the opposite side...
Friday, October 21, 2016 by MYA

Physics
A neutron with mass 1.67e-27 kg moving with speed 5.0 × 101 km/s makes a head-on collision with a boron nucleus, originally at rest, with mass 1.66e-26 kg. A) If the collision is completely inelastic, so the particles stick together, what is the final kinetic energy of ...
Friday, October 21, 2016 by Anonymous

Physics
A student has a small battery-powered alarm buzzer. The student throws the buzzer toward a stationary wall (possibly due to frustration following a physics midterm examination). The buzzer emits sound with a frequency of 74 Hz, and the wall reflects the sound. If the buzzer is...
Friday, October 21, 2016 by Po

physics
A rookie quarterback throws a football with an initial upward velocity component of 15.9 m/s and a horizontal velocity component of 18.0 m/s . Ignore air resistance. a) How much time is required for the football to reach the highest point of the trajectory? c) How much time (...
Friday, October 21, 2016 by Kiran

physics qui
The radius of the Earth is 6.37×1000000 m and its average dencity is 5.517×1000kg/m×​;m×m.calculate the mass of earth to correct significant figures.
Friday, October 21, 2016 by Anonymous

physics
The characteristics of a horizontal and undamped spring-block system are k=400N/m and M=0.3kg.The position of the block is determined by its abscissa along an x'ox axis. When the spring has its natural length then x=0. a) the spring is stretched by shifting the block by 10...
Friday, October 21, 2016 by vicky

physics
what is the minimum effort required to raise a load of 5kg in an ideal pulley system taking gravity to be 10m/s/s
Friday, October 21, 2016 by francis

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