# Homework Help: Science: Physics

## Recent Homework Questions About Physics

Physics
State the reason why a steel sphere resting on a horizontal surface is said to be in neutral equilibrium.

Physics
The wheels of a skateboard roll without slipping as it accelerates at 0.45 m/s2 down an 75-m-long hill. If the skateboarder travels at 1.8 m/s at the top of the hill, what is the average angular speed of the 2.6-cm-radius whe els during the entire trip down the hill? I first ...

physics
Calculate the magnitude of the force FM required of the "deltoid" muscle to hold up the outstretched arm shown in the figure below. The total mass of the arm is 2.8 kg and θ = 11°. d=12cm D=24cm

Physics
A wire with cross sectional area 1.00 cm2 stretches 0.500% of its length when it is stretched with a tension of 20.0 N. What is the Young's modulus of this wire?

physics
Children slide down a frictionless water slide that ends at a height of 1.80 m above the pool. If a child starts from rest at point A and lands in the water at point B, a horizontal distance L = 2.46 m from the base of the slide, determine the height h of the water slide.

Physics
A square metal plate with length L= 0.14 m on each side is pivoted about an axis through the center point O, perpendicular to the plate. Calculate the net torque about this axis due to the three forces shown that act at the corners, with magnitudes F1 =18 N, F2 = 28 N, and F3...

Physics
A rigid rod of mass 0.2 kg and length 1.5 m is suspended by wires at each end. The wireshave equal rest length. The wire on the left end of the rod has Young’s modulus4*10^11Pa, while the one on the right end has Young’s modulus2*10^11Pa. A 2 kg mass is hung fromthe beam. ...

Physics
Three children are riding on the edge of a merry–go–round that is 84 kg, has a 1.40–m radius, and is spinning at 20.0 rpm. The children have masses of 21.0, 24.0, and 29.0 kg. If the child who has a mass of 24.0 kg moves to the center of the merry–go–round, what is ...

physics
A child with a mass of 46 kg is riding on a merry-go-round. If the child has a speed of 3 m/s and is located 2.2 m from the center of the merry-go-round, what is the child's angular momentum? ____kg2/s

physics
A variable-speed drill, initially turning at 150 rpm, speeds up to 1300 rpm in a time interval of 1.0 s. What is its average rotational acceleration? ______rpm/s2

PHYSICS
A uniform ladder of length 20.0m and weight 750 N is propped up against a smooth vertical wall with its lower end on a rough horizontal surface. The coefficient of friction between the ladder and this horizontal surface is 0.40. (a) Draw a diagram for the ladder showing all ...

PHYSICS
A ball of mass 0.15kg is dropped from a height of 1.0m onto a flat surface and rebounds to a height of 0.35m. Calculate: (a) The speed of the ball just before the impact, (b) The speed of the ball just after impact, (c) The change of momentum, (d) The force of impact, if the ...

Physics
A ball roll down a hill with a constant acceleration of 20m/s if the ball start from rest. What is it velocity at the end of 4.05

PHYSICS(MCAT)
an area several km from an electricity generating station requires 120kw power on average the total resistance is line is 0.4 ohm calculate power loss if the transmission is made ata low voltage 240V

Physics
A car of mass 1000 kg moving with a velocity of 30m/s applies break and stop after 3s. Find the magnitude of retarding force, the distance travelled by the car before it came to rest and the work done by the breaking force.

Physics
Three children are riding on the edge of a merry–go–round that is 84 kg, has a 1.40–m radius, and is spinning at 20.0 rpm. The children have masses of 21.0, 24.0, and 29.0 kg. If the child who has a mass of 24.0 kg moves to the center of the merry–go–round, what is ...

physics
a car at 54 km\h is 60 km behind a truck traveling at 10 m\s. how long will it take the car to reach the truck?

physics
a car at 54 km\h is 60 km behind a truck traveling at 10 m\s. how long will it take the car to reach the truck?

physics
computer-controlled display screens provide drivers in the Indianapolis 500 with a variety of information about how their cars are performing. for instance, as ac car is going through a turn, a speed of 221 mi/h (98.8m/s) and centripetal acceleration of 3.00g are display. ...

Physics
The block of mass 2.13615 kg has an acceler- ation of 3.7 m/s2 as shown. What is the magnitude of F? Assume the acceleration due to gravity is 9.8 m/s2 and the surface is frictionless. Answer in units of N.

Physics
1.     Compare the slope of the distance vs. time graph to the average of all your velocity values. Are they close? Why or why not? What does the slope of a distance (or displacement) vs. time graph mean? Explain the answer using your data.

physics
A variable-speed drill, initially turning at 150 rpm, speeds up to 1300 rpm in a time interval of 1.0 s. What is its average rotational acceleration? ______rpm/s2

physics
A child with a mass of 46 kg is riding on a merry-go-round. If the child has a speed of 3 m/s and is located 2.2 m from the center of the merry-go-round, what is the child's angular momentum? ____kg·m2/s

Physics
would apppeciate very much is anyone can help me in the below question. thanks. A man runs round a circular track at a constant speed. Would like to know how to drawn locus of the points representing the magnitude ‘d’ of the displacement of the man from the starting ...

Physics
two blocks (a and b) are in contact on a horizontal frictionless surface. a 60N constant horizontal force is applied to A. the mass of a is 3.0 kg and the mass of b is 15 kg. what is the magnitude of the force of a on b

physics
If the rotational speed of a CD changes from 550 rpm to 200 rpm as it plays 30 minutes of music, what is the CD's average rotational acceleration?

physics
A frog jumps at 0.6 m/s at an angle of 20 degrees and lands on a level surface. How far does the frog jump?

Physics
A car is backing up at a rate of 10km/hr. If the driver looks through his rear-view mirror, how fast does a tree, which is behind him, appear to approach him?

physics
A ball bounces off the edge of a table at an initial velocity of 1.5 m/s at an angle of 30 degrees above the table, falling to the floor 75 cm below. How long will the ball be in the air?

physics
What is the rotational speed of the hour hand on a clock?

physics
A child with a mass of 17 kg sits at a distance of 1 m from the pivot point of a seesaw. Where should a 15 kg child sit to balance the seesaw?

physics
Robin is standing terrified at the end of a diving board, which is high above the water. If Robin has a mass of 56 kg and is standing 1.5 m from the board's pivot point, what torque is Robin exerting on the board?

physics
A 1400 kg car is traveling at 28 m/s around a curve with a radius of 116 m. What is the angular momentum of the car?

Physics
After skiding down a snow-covered hill on an inner tube, Ashley is coasting across a level snowfield at a constant velocity of +3.4 m/s. Miranda runs after her at a velocity of +4.0 m/s and hops on the inner tube. How fast do the two of them slide across the snow together on ...

physics
A two-stage rocket moves in space at a constant velocity of +4890 m/s. The two stages are then separated by a small explosive charge placed between them. Immediately after the explosion the velocity of the 1380-kg upper stage is +5660 m/s. What is the velocity (magnitude and ...

physics
A 40.2-kg skater is standing at rest in front of a wall. By pushing against the wall she propels herself backward with a velocity of -1.84 m/s. Her hands are in contact with the wall for 1.17 s. Ignore friction and wind resistance. Find the average force she exerts on the wall...

physics
The work that a force does by acting on an object is equal to what? 1) the product of force (in the direction of motion) and distance and is negative if the force and motion are in the same direction 2) the product of force (in the direction of motion) and distance and is ...

physics
A railroad car of mass 2.15 ✕ 104 kg moving at 3.15 m/s collides and couples with two coupled railroad cars, each of the same mass as the single car and moving in the same direction at 1.20 m/s. (a) What is the speed of the three coupled cars after the collision? ...

Physics
You're tour director for a lunar trip, and want to award your passengers with certificates commemorating their crossing the point where the Moon's gravity becomes stronger than Earth's.How far from Earth should you award the certificate? Express your answer in meters.Express ...

Physics
How will the elastic potential energy and the gravitational potential energy change at different points in the oscillation?

Physics honors
If a racer runs at an average speed of 7m/a how far will she run in 1 min 45 seconds?

Physics
A uniform ladder of length 20.0m and weight 750 N is propped up against a smooth vertical wall with its lower end on a rough horizontal surface. The coefficient of friction between the ladder and this horizontal surface is 0.40. (a) Draw a diagram for the ladder showing all ...

Physics
A ball of mass 0.15kg is dropped from a height of 1.0m onto a flat surface and rebounds to a height of 0.35m. Calculate: (a) The speed of the ball just before the impact, (b) The speed of the ball just after impact, (c) The change of momentum, (d) The force of impact, if the ...

physics
In a Broadway performance, an 85.0-kg actor swings from a R = 4.45-m-long cable that is horizontal when he starts. At the bottom of his arc, he picks up his 55.0-kg costar in an inelastic collision. What maximum height do they reach after their upward swing?

physics
You shoot a 56 gram dart vertically upwards from a catapult with a spring constant of 335 N/m. The catapult is initially stretched from the equilibrium point by 27 cm. What is the height above the starting point reached by the dart?

Physics
A) Under what condition is average velocity equal to instantaneous velocity? B) Does the speedometer of car measure speed or velocity? Explain. C) Can the magnitude of a vector be less than the magnitude of any of its components? Explain.

Physics
A) Under what condition is average velocity equal to instantaneous velocity? B) Does the speedometer of car measure speed or velocity? Explain.

Physics
Under what condition is average velocity equal to instantaneous velocity?

Physics
A stone is thrown from the top of a tower of height 60m with velocity 40m/s at an angle of 30 degree above the horizontal. Calculatethe time taken by the stone to hit the ground. At what distance from the foot of the tower the stone hits the ground.

Physics
A man walking on a road at 3km/hr encounters rain falling vertically at 18km/hr. At what angle should he hold the umbrella to protect himself from rain?

Physics
You toss a ball from your window 8m above the groun. When the ball leaves your hand, ut is moving at 10m/s at an angle of 20 degree below the horizontal. How far horizontally from your window will the ball hit the ground? Ignore air resistance. Plz answer it fast . It's my ...

Physics
A river flows from south to north at 5km/hr. On this river a boat is heading east to west perpendicular to the current at 7km/hr. As viewed by an eagle hovering at rest over the shore, how fast and in what direction is the boat travelling?

physics
If the effect of the air resistance acting on falling raindrops is ignored, then we can treat raindrops as freely falling objects. a.) Rain clouds are typically a few hundred meters above the ground. Estimate the speed with which raindrops m/s, km/hr, and mi/hr? b.) From your ...

physics
A uniform vertical glass tube open at the lower end and sealed at the lower end is lowered into sea water thus trappung the air int he tube . It is observed that when the tube is submerged to a depth 10 meters the sea water has entered the lower half of the tube . To what ...

physics
Calculate the component of a force of 200N at a direction of 60degre to the force

Physics
A bullet is fired with an initial speed of 200 m/s. If a target is 500ft away, at what angle should the rifle be raised in order to hit the target?

Physics
A point mass block slides without friction on the loop-de-loop track of radius R as shown. From what height h must it be released from rest in order to make it around the loop without leaving the track? Show the equation and then plug the numbers into that equation and show ...

Physics
Two identical massless springs of constant k = 200N/m are fixed at opposite ends of a level track, as shown. A 5 kg block is pressed against the left spring, compressing it by 0.15m. The block is then released from rest. The entire track is frictionless except for the region ...

Physics
How much work must be performed by a hand or other such agent to move the 8kg block very slowly 10 cm to the right if the attached spring was initally relaxed? Let k = 200 N/m and mK = 0.5. Show the equation and the plug the numbers into the equation and then the answer at the...

Physics
A 3 kg object initially at rest is acted on by a non-constant force which causes it to move 3 m. The force varies with position as shown in the figure. a) How much work is done on the object by this force? b) What is the final speed of the object as it arrives at x=3m? Assume ...

Science-physics
A bottle weighs 35g when empty,95g when filled with water and 119g when filled with an organic liquid. What is the capacity of the bottle: A-60cm cube B-84cm cube C-130cm cube D-154cm cube

physics
Sam and Sue are running side by side in a marathon. They are running at a constant velocity of 10 km h . What is Sue's relative velocity to Sam? A) 0 km/h B) 5 km/h C) 10 km/h D) 20 km/h

Physics
A 150 kg body is at rest and covers the constant force needed to impart a velocity of 8m/s to it in 5s.

Physics
A ball of mass 8 kg moving with a speed of 2m/s and rebounds with the same speed.Determine the impulse experienced by the ball. (a)20.0kg/m (b)10.0kg/m (c)0.01kg/m (d)1.3kg/m

Physics
A ball of mass 8 kg moving with a speed of 2m/s and rebounds with the same speed.Determine the impulse experienced by the ball.

physics
The work that a force does by acting on an object is equal to what? 1) the product of force (in the direction of motion) and distance and is negative if the force and motion are in the same direction 2) the product of force (in the direction of motion) and distance and is ...

Physics
Since moment of inertia is a scalar quantity, a compound object made up of several objects joined together has a moment of inertia which is the scalar sum of the individual moments of inertia. A) A wooden cylinder has mass m and radius R. To be used as a machine part, its ...

Physics
A ball is tied to a string and whirled in a horizontal circle at a constant 4 revolutions per second. Categorize the following according to whether they are 0 in value, constant in value, or change: v: linear speed (scalar) v: linear velocity (vector) ar: radial (centripetal) ...

Physics (Mechanics)
A student of mass M = 62 kg takes a ride in a frictionless loop-the-loop at an amusement park. The radius of the loop-the-loop is R = 19 m. The normal force by the track on the student at the top of the loop-the-loop is N1 = 100 N Find the speed of M at the top of the loop. ...

Physics
What the hell are u teaching people!!! :)

Physics (Mechanics)
A 905 kg car moves in a circle of radius 13.1 meters in a flat parking lot. If the car can travel at 9.1 m/s without slipping, what is the force of friction between each tire and the parking lot? What is the coefficient of friction between each tire and the lot? (Remember ...

physics
A block with a mass of 0.306 kg is attached to a spring of spring constant 444 N/m. It is sitting at equilibrium. You then pull the block down 4.50 cm from equilibrium and let go. What is the amplitude of the oscillation?

physics
A box is being accelerated across a rough, level surface. A force is being applied to the box in an upward and a rightward direction (as shown below). This force makes an angle of 30 degrees with the horizontal. The force of friction experienced by box would be equal to______.

Physics
Three charges +2q, -q and -q are placed at the vertices of an equilateral triangle. What is the electric field and the potential at the circumcenter of the triangle?

physics
If a hair dryer is rated at 900 W, how much energy does it require in 5 minutes?

physics
When a force acts on an object from an angle other than either 0° or 180° to the direction of motion: 1) The force is perpendicular to the direction of motion, so no work gets done. 2) The parallel and perpendicular component of the force both do work. 3) The perpendicular ...

physics
Which of the following is true about frictional forces? 1) They are stored as frictional potential energy. 2) They can decrease kinetic energy. 3) They produce heat potential energy. 4) They eventually convert to electromagnetic potential energy. 5) They can increase kinetic ...

physics
The work that a force does by acting on an object is equal to what? 1) the product of force (in the direction of motion) and distance and is negative if the force and motion are in the same direction 2) the product of force (in the direction of motion) and distance and is ...

Ap physics
Determine the mass of the earth from the known period and the distance of the moon

Physics
Three different masses are attached to a spring which hangs down vertically from the ceiling. A metric ruler hangs from the ceiling next to the spring and measures how far from the ceiling the sping hangs. When a 110 N weight is attached to the spring, the spring reaches the ...

Physics
A knight sits on a castle wall during a siege. To while away the time, he notes that boulders catapulted from below land on the top of his wall with a vertical velocity of 7.5 m/s. If he is 34 m above the catapult, what is the initial velocity of the boulders? The acceleration...

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.

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 .

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?

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

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...

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 ...

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...

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?

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 ...

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?

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+...

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?

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?

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?

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?

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

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.

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.

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