# Homework Help: Science: Physics

## Recent Homework Questions About Physics

**Physics**

a 294 kg crate is released from rest and hits the ground 1.18 m below after 4.10 s. What is the mass of the crate to the left of the pulley? Assume the rope and pulley are massless.

**physics**

An ideal gas has the following initial conditions: Vi = 490 cm3, Pi = 5 atm, and Ti = 100°C. What is its final temperature if the pressure is reduced to 1 atm and the volume expands to 1000 cm3?

**Physics**

A 3 kg book is resting on a table. What force does the table exert on the book?

**Physics**

A 45kg skier is sliding down a 37 degree ski slope starting from rest. She crossed the 25m in 5.0s. Ignoring air resistance, Find all the forces on the skier.

**Physics**

The large disk-shaped flywheel illustrated below has a radius R of 0.25 m. It is made to spin by the small wheel that contacts it at its rim. The small wheel applies a constant force of 1430 N. Friction in the bearing exerts a retarding torque 22 Nm on the large wheel. If the ...

**Physics**

Suppose your car was mired deeply in the mud and you wanted to use the method illustrated in the figure to pull it out. (a) What force in newtons would you have to exert perpendicular to the center of a rope to produce a force of 10,000 N on the car if the angle is 1.80°? ...

**physics**

There are two crates are sliding down a ramp. If the crate at the top has a mass of 11.5 kg and friction is 0.20. The other has a mass of 23 kg and friction is 0.10, what is the tension in the string? Assume the string is massless.

**physics**

motion

**Physics**

An object initially rotating at an angular speed of 1.6 rad/sec turns through 30 revolutions during the time it experienced an angular acceleration of 0.32 rad/s^2. a) For how much time did the acceleration last? b) What was the final angular speed?

**Physics**

What is the angular speed of the earth as it orbits the sun a) in radians/second? b) in degrees per day?

**Physics**

What is the reaction of the earth pulling down on a pen that is lying on a table

**Physics**

Three liters of nitrogen combine with 9 L of hydrogen to form 6 L of ammonia. If the molecules of nitrogen and hydrogen have two atoms each, how many atoms of hydrogen and nitrogen are there in one molecule of ammonia? ____ atoms of hydrogen ____ atoms of nitrogen

**Physics**

A mass-spring system undergoes simple harmonic motion with amplitude A.Does the total energy of the system change if the mass doubled but the amplitude is unchanged? Does the kinetic and potential energies depends on the mass? Explain.

**Physics**

The distance between two telephone poles is 50.0 m. When a 0.500-kg bird lands on the telephone wire midway between the poles, the wire sags 0.14 m. Ignore the weight of the wire. 1)How much tension does the bird produce in the wire? (Express your answer to two significant ...

**Physics**

A certain number of identical resistors are connected in series and their total resistance is measured. When the resistors are disconnected and re-connected in parallel, their total resistance drops to one-percent of the value measured when they were connected in series. How ...

**physics**

Two crates rest on top of one another.There is a crate of mass 4.62 kg on top of another crate of mass 2.19 kg. The coefficient of friction between the lower crate and the floor is μk = 0.440 and the coefficient of static friction between the two crates is μs = 0.870. If the...

**Physics**

A car uniformly accelerates from 0 to 27.0 m/s. A 68.0-kg passenger experiences a horizontal force of 390.0 N. 1)How much time does it take for the car to reach 27.0 m/s? (Express your answer to three significant figures.) My teacher didn't explain how we could ever find the ...

**Physics**

Suppose that instead of our sun, our star were a giant star such as Betelgeuse. The mass of Betelgeuse is estimated to be about 20 times that of our sun. With earth in the same orbit? With its same mass, how long would our year be in earth days if we orbited Betelgeuse?

**Physics**

A) the earth year is 365.25 days long. How long would our year be if earth followed the same orbit, but was only the mass of Mars? Answer this in earth days. B) How long would our year be if earth were the same mass, but had the orbital distance of mercury Answer this in earth...

**Physics**

At a height of 500km above earth, a satellite will orbit the earth once every 95 minutes. Find the mass of the earth based on this idea. B) How far above earth's surface would a satellite need to orbit so that it revolves at exactly the same rate as the earth's rotation?

**physics (CHECK MY WORK PLEASE ASAP)**

An object of mass 1.00kg is moving over a horizontal circular path of radius 2.00m, with a speed of 3.00ms^-1. Determine: (a) its centripetal acceleration (b) its kinetic energy (c) its period (d) its angular velocity a: 3.00^2/2.00 = 4.5 ms^-1 b: 0.5 × 1.00 × 2.00^2 × 3.00...

**Physics**

Two cars approach along icy streets which meet at a right angle to one another. The cars collide and stick together. One car has a mass of 1200 kg and had a speed of 30 km/h in the +x direction before the collision. The second car has a mass of 1500 kg and was traveling in the...

**Physics**

A particle accelerates from rest at a constant rate for some time and attains a velocity of 8 meter per second. Afterwards it decelerates with the consent rate and comes to rest. If the total time taken is 4 second then what is the total distance covered by the particle?

**physics**

A box slides down a frictionless 35 degree incline. Determine its acceleration. If the incline is 10.0 m long and the box starts from rest, how much time does it take to get to the bottom?

**Physics**

A 10 kg object (m1) initially moving to the right at 20 m/s makes a totally elastic head on collision with a 15 kg object (m2) which was initially moving to the left at 5 m/s. Find the final velocities of each object. HINT: Treat this as a one-dimensional problem. Help ASAP ...

**Physics**

Two cars approach along icy streets which meet at a right angle to one another. The cars collide and stick together. One car has a mass of 1200 kg and had a speed of 30 km/h in the +x direction before the collision. The second car has a mass of 1500 kg and was traveling in the...

**Physics**

Three carts of masses 4kg, 10 kg, and 3 kg move on a frictionless horizontal surface with initial speeds of 5 m/s, 3 m/s, and 4 m/s. If the carts all stick together after the collisions, what will be the final velocity of the combined mass? Help ASAP please. Step by step to ...

**Physics**

Show that the kinetic energy of an object can be written in terms of the momentum as KE = p2/2m. Help ASAP please. Step by step to get the answer

**Physics**

a) What is the ratio of the momentum of a 3kg mass moving at 3 m/s to that of a 2 kg mass moving at 4 m/s? b) What is the ratio of the respective kinetic energies? Help ASAP please!! Step by step to get the answers

**Physics**

One afternoon, a couple walks three-fourth of the way around a circular lake, the radius of which is 1.45km. They start at the south side of the lake and head due east at the beginning of their walk. (a) What is the distance they travel? (b) What are the magnitude and ...

**Physics**

A boat crosses a river 1.5km wide in 15mins. If the river flows at 2km/hr calculate the velocity of the boat.

**physics**

An object of mass 1.00kg is moving over a horizontal circular path of radius 2.00m, with a speed of 3.00ms^-1. Determine: (a) its centripetal acceleration (b) its kinetic energy (c) its period (d) its angular velocity

**Physics**

Two hockey pucks of equal mass are involved in a perfectly elastic, glancing collision, as shown in the figure below. The orange puck is initially moving to the right at voi = 3.95 m/s, when it strikes the initially stationary blue puck, and moves off in a direction that makes...

**Physics FRICTION FORCE AND N-2ND LAW**

A balloon has a weight of 1250 N, and the lifting force on it is 3525N. If the air resistance is 15N, what is the acceleration of the balloon? (Notice fg=mg) 3525-15=3515 3515/1250= 2.81 ???? A pulling force on a case is 1653 N while the friction force is 765 N on the case. If...

**physics**

A mango fruit drops from the top of it's tree which is 40 m. How long does it takes to reach the ground

**Physics PROJECTILE AND CIRCULAR MOTION**

1.13g plastic stopper is attached to a 0.93-m string. The stopper is swung in a horizontal circle, making one revolution in 1.18s(period T). Find the tension force(equivalent to the centripetal force)exerted by the string on the stopper? (V=2(pie)r/T)? 2. A football is thrown ...

**Physics**

A child standing on a platform holds a rope taut at an angle θ to the vertical. The child swings from the platform starting from rest. When the child swings through the lowest position, the tension in the rope is 1.9 times the child's weight. Determine the value of θ.

**Physics**

Calculate the force of earths Gravity on a 2.00 earth radii above the earth surface if it's mass is 1850kg.

**AP physics**

Astronauts who spend long periods in outer space could be adversely affected by weightlessness. One way to stimulate gravity is to shape the spaceship like a cylindrical shell that walking on the inside surface. Explain how this simulates gravity. Consider (a) how object fall...

**physics**

An ideal gas has the following initial conditions: Vi = 490 cm3, Pi = 5 atm, and Ti = 100°C. What is its final temperature if the pressure is reduced to 1 atm and the volume expands to 1000 cm3? ______ °C

**physics**

Three liters of nitrogen combine with 9 L of hydrogen to form 6 L of ammonia. If the molecules of nitrogen and hydrogen have two atoms each, how many atoms of hydrogen and nitrogen are there in one molecule of ammonia? ____ atoms of hydrogen ____ atoms of nitrogen

**physics**

1. A bullet of mass 10 g is fired vertically upward and it reaches to the highest point in 10 seconds. Which of the following figures is nearer to its maximum height above the firing position? A) 10 m B) 22 m C) 30 m D) 42 m E) None of the above

**physics**

A bomber drops a bomb from an aircraft flying at 2000Km/h with an altitude of 7 Km. The speed at which the bomb will strike the earth would be. a) Greater than 2000Km/h b) Less than 2000 Km/h c) Equal to 2000 Km/h d) Can not compare with the given data

**physics**

A duck is swimming across a river. The duck can swim at maximum speed of 2m\s in still water. If the duck i swimming as hard as possible straight across a river that running at 4m\s, what is the duck's overall speed, relative to the goose sitting on the river bank?

**physics**

A boat is heading directly North acroos a river at 5km\h. The river is flowing east at 3km\h. a) what is the actual velocity of the boat? b) how far down stream does it land if the trip takes 0.5 hrs. c) how wide is the river?

**physics**

A force of 300N lifts a mass of 120kg with help of lever whose length is 2.4 m.The distance between fulcrum and mass is a) 40cm b) 48cm c) 80cm d) 171cm

**physics**

a body is projected with velocity v1 from a point a at the same time another body is projected vertically upwards with velocity v2 the point b lies vertically below the height the point for both the bodies to collide 2/v should be

**AP physics**

The earth moves faster in its orbits around the sun in January, or in July? Explain [Note: this is not much of a factor in producing seasons - the main factor is the tilt of the earths axis relative to the plane of its orbit.]

**AP physics**

The sun is below us at a magnitude of nearly a line with the earth center. Are we then Heavier at midnight due to the sun's gravitational force on us, than we are at noon? Explain

**Physics**

Why is more fuel required for spacecraft to travel from the earth to the moon than to return from the moon to the earth?

**Physics**

Does an apple exert a gravitational force on the earth? If so, how large a force? Consider an apple (a) Attached to a tree and (b) falling.

**AP physics**

Astronauts who spend long periods in outer space could be adversely affected by weightlessness. One way to stimulate gravity is to shape the spaceship like a cylindrical shell that walking on the inside surface. Explain how this simulates gravity. Consider (a) how object fall...

**Physics**

A ball A having a speed of 44.0 ms-1 collides with another ball, B, of the same mass which is initially at rest. After the collision A is deflected, 45.0 from its initial direction and B moves off at an angle of 30.0° to the original direction of A. a. What is the nature ...

**Physics**

A ball A having a speed of 44.0 ms-1 collides with another ball, B, of the same mass which is initially at rest. After the collision A is deflected, 45.0 from its initial direction and B moves off at an angle of 30.0° to the original direction of A. a. What is the nature ...

**Physics**

A dike in Holland springs a leak through a hole of area 0.80 cm2 at a depth of 1.4 m below the water surface.How much force must a boy apply to the hole with his thumb to stop the leak? Could he do it?

**Physics**

A cube of ice, 28 cm on each side,is melted into a measuring cup. What is the volume of the liquid water -------cm^3

**physics**

A cube with a mass of 40 g is made from a metal with a density of 6 g/cm3. What is the volume of the cube and the length of each edge? ----volume cm^3 -----length cm^3

**Physics**

A ship is first seen on a radar screen to be 9 km east of the radar site. Some time later, the ship is at 18km northwest. What is the displacement of the ship from the first location it is seen at? 25.2 km (INSERT ANGLE HERE?!?) degrees north of west

**Physics**

A ship is first seen on a radar screen to be 9 km east of the radar site. Some time later, the ship is 18 km northwest. What is the displacement of the ship from the first location it is seen at?

**physics**

A cube of ice, 28 cm on each side, is melted into a measuring cup. What is the volume of the liquid water? ------cm3

**physics**

A solid ball with a volume of 0.1 m3 is made of a material with a density of 2800 kg/m3. What is the mass of the ball? -----kg

**Advanced Physics**

What are the displacements for the following vectors? I. A vector moving 45 degrees northeast at a velocity of 3m/s and the turns 30 degrees southeast

**physics (urgent)**

A flywheel with a moment of inertia of 1.00kg m^2 is rotating at 100 rpm. What torque is required to bring it to rest in 10.0 revolutions?

**PHYSICS**

An aeroplane makes in emergency landing without landing gear. If the aeroplane touches down with a horizontal speed of 60.0ms^-1 and the coefficient of friction for aluminium on asphalt is μ = 0.500, how far will the aeroplane slide before coming to rest? You may assume that ...

**Physics**

An object of mass 1.00kg is moving over a horizontal circular path of radius 2.00m, with a speed of 3.00ms^-1. Determine: (a) its centripetal acceleration (b) its kinetic energy (c) its period (d) its angular velocity

**Physics - Gravitation**

Vesta, a minor planet in the Asteriod Belt between Mars and Jupiter, has a mean radius of 525 km and mass of 2.59 X 10^20 kg. The Dawn Spacecraft (m = 1240 kg) orbited Vesta in 2011 & 2012. How much energy did the spacecraft expend going from the 2750 km orbit to a 210 km ...

**Physics Gravitation Question**

Vesta, a minor planet in the Asteriod Belt between Mars and Jupiter, has a mean radius of 525 km and mass of 2.59 X 10^20 kg. The Dawn Spacecraft (m = 1240 kg) orbited Vesta in 2011 & 2012. A. Find the local acceleration due to gravity at the mean surface of Vesta. What is the...

**Physics Gravitation Question**

Vesta, a minor planet in the Asteriod Belt between Mars and Jupiter, has a mean radius of 525 km and mass of 2.59 X 10^20 kg. The Dawn Spacecraft (m = 1240 kg) orbited Vesta in 2011 & 2012. Find the local acceleration due to gravity at the mean surface of Vesta. What is the ...

**Physics**

A particle of mass m1 = 2.5 kg moving along the x axis collides with a particle of mass m2 = 4.9 kg initially at rest. The incoming particle is deflected in the direction 22 degrees above the x axis, whereas the target particle moves off at 15 m/s at 37 degrees below the x ...

**Physics**

A ship is first seen on a radar screen to be 9 km east of the radar site. Some time later, the ship is at 18 km northwest. What is the displacement of the ship from the first location?

**physics**

A car is traveling at 60.6 mph on a horizontal highway. The acceleration of gravity is 9.8 m/s2. If the coefficient of friction between road and tires on a rainy day is 0.056, what is the minimum distance in which the car will stop? Answer in units of m.

**Physics**

A horizontal forces of magnitude 500N pulls two blocks of masses m1=10 kg and m2=20 kg which are connected by the light inextensible string and lying on the horizontal frictionless surface. Find the tension in the strings and acceleration of each mass when forces is applied on...

**physics**

a duck is swimming across a river.The duck can swim at maximum speed of 2m\s in still water. If the duck is swimming as hard as possible straight across a river that is running at 4m\s, what is the duck's overall speed, relative to the goose sitting on the river boat?

**physics**

A body is in equilibrium under the action of three force..one force is 4.0N acting due east and one is 5.0N in direction, 60°NE.calculate the magnitude of the third force.

**Physics**

If your hands are wet and no towel is handy, you can remove some of the excess of water by shaking them. Why does this get rid of it?

**Physics**

An airplane pilot wishes to fly due west. A wind of 80km/hr is blowing towards the south. a) If the speed of llane in air is 320km/hr, in which direction should the pilot head? b) What is the speed of plane over the ground? (Illustrate with diagram)

**applied physics**

what angle do blue light wavelength of 460 nm and red light 680 nm disperse upon entering from vacuum to a dispersion medium with n(blue)=1.349 and n(red)=1.213 at an incident angle of 20 degree?

**Physics**

A sample of ice at 0-degree melts after absorbing kJ of heat. How many kg of H20 are contained in the sample?

**Physics**

How much energy must be removed from 30 L of liquid water at 0-degree celsius in order to convert it to ice?

**physics**

An ideal gas has the following initial conditions: Vi = 490 cm3, Pi = 5 atm, and Ti = 100°C. What is its final temperature if the pressure is reduced to 1 atm and the volume expands to 1000 cm3? -----°C

**Physics**

An airplane has a mass of 2.8×106 kg , and the air flows past the lower surface of the wings at 81 m/s . Part A: If the wings have a surface area of 1100 m2 , how fast must the air flow over the upper surface of the wing if the plane is to stay in the air? Express your answer...

**Physics**

In physics, work is defined as the product of the A) net force and the distance traveled B) net force parallel to the motion and direction traveled C) net force parallel to the motion and the time it is applied

**AP Physics**

The length of the cannon barrel is 1.7 m and the cannon is aimed at a 38◦angle from the ground.The acceleration of gravity is 9.8 m/s^2. If Dread Pirate Roberts tells you he wants the ball to leave the cannon with speed V-not = 76 m/s, what mass cannon ball must you use? ...

**Physics**

A "swing" ride at a carnival consists of chairs that are swung in a circle by 17.9 m cables attached to a vertical rotating pole, as the drawing shows. Suppose the total mass of a chair and its occupant is 193 kg. (a) Determine the tension in the cable attached to the chair. (...

**Physics**

) A car is traveling on a straight, horizontal road at 20 m/s when the driver slams on the brakes. The force of friction between the car and the road is 900 N. The mass of the car is 1800 kg. (a) Make a free body diagram for the car on the set of axes provided. (b) How far ...

**physics**

if a swimmer can swim in still water at a speed of 7.3 m/s and he intends to swim across a river that has a downstream current of 2.5 m/s what is the swimmers direction?

**Physics**

For a certain projectile, the horizontol range is twice in magnitude of the maximum height attained by it. Find its angle of projection.

**Physics**

Rain drops hitting the side window of a car in motion often leave diagonal streaks if there is no wind. Why?

**Physics**

An electric train leaves a station starting from rest and attains a speed of 72km/hr in 10 second. Then it undergoes uniform retardation for 20 second to come to halt at the next station then calculate i) the distance between the train stations. ii) the average velocity of train.

**Physics**

Two workers pull horizontally on a heavy box, but one pulls twice as hard as the other. The larger pull is directed at 25 degree west of north and the resultant of these two pulls is 350 netwon directly northward. Use vector components to find the magnitude of each of these ...

**Physics**

Two boxes are stacked in an elevator that is accelerating downwards at 3.49m/s/s. A smaller 3.06kg box is on top and a larger 9.93kg box is on bottom. Find the magnitude and direction of the force that the smaller mass exerts on larger.

**Physics**

Ice floats with one ninth of its volume above water. What is the relative density of ice?

**Physics**

A flywheel with a moment of inertia of 1.00kg m^2 is rotating at 100 rpm. What torque is required to bring it to rest in 10.0 revolutions?

**PHYSICS (REALLY DIFFICULT PLEASE HELP)**

An aeroplane makes in emergency landing without landing gear. If the aeroplane touches down with a horizontal speed of 60.0ms^-1 and the coefficient of friction for aluminium on asphalt is μ = 0.500, how far will the aeroplane slide before coming to rest? You may assume that ...

**Physics**

An object of mass 1.00kg is moving over a horizontal circular path of radius 2.00m, with a speed of 3.00ms^-1. Determine: (a) its centripetal acceleration (b) its kinetic energy (c) its period (d) its angular velocity

**Physics**

A ball of mass 0.1kg dropped from a building of 8m high unto a hard floor bounces back to a height of 2m. Calculate the change in momentum , if the ball is in constant with the floor of 0.1s, what is the force exerted on the body . (g = 10ms)

**physics**

A vector moving 45 degrees northeast at a velocity of 3m/s and the turns 30 degrees southeast with a velocity of 10m/s.

**Physics**

At the surface of a certain planet, the gravitational acceleration g has a magnitude of 12.0 m/s^2. A 21.0-kg brass bell is transported to this planet. What is (a) the mass of the brass ball on the Earth and on the planet, and (b) the weight of the brass ball on the Earth and ...

**Physics**

A fire helicopter carries a 358 kg bucket at the end of a 10.4 m long cable. When the helicopter is returning from a fire at a constant speed of 51.4 m/s, the cable makes an angle of 23.7◦ with respect to the vertical. Find the horizontal force exerted by air resistance on ...

**Physics**

Why may someone not be able to cooled by evaporation?