# Homework Help: Science: Physics

## Recent Homework Questions About Physics

**Physics**

Suppose you have a pinhole camera which is 5 cm long between the hole and the film. You photograph a 1 cm long bug that is 10 cm in front of the pinhole. How long will the image of the bug be on the film?

**Physics 11**

A 62kg cyclist changes the speed of a 12kg bicycle from 8.2m/s to 12.7m/s. Determine the work done. I used change in energy = work to find work against inertia which was 3479.85 Then I used V^2=V.^2 + 2ad to get ad=47.025 I then used W=mad to get work against friction, my ...

**Physics 11**

A girl pushes her little brother on his sled w/ a force of 35N for 840s. How much work does she do if the force of friction I'd 27N? I subtracted the force of friction from the applied force to get my net force of 8N but I don't know where to go from there... Thank you :)

**Physics 11**

A 90kg basketball player carries about 720J of kinetic energy when running down the court. If the coefficient of kinetic friction between good runners & the floor is .600, how far does the player skid when trying to stop? Hint: what work was done by friction in bringing the ...

**physics**

a simple pendulum has a period of 2.0s and magnitude of swing 5cm.find i-the velocity of the bob ii-the acceleration of the bob

**Physics**

A car is traveling with a kinetic energy if 2200 J. If a braking force of 1100 N is applied to the car, how far will the car travel before it stops?

**Physics**

A car is traveling with a kinetic energy if 2200 J. If a braking force of 1100 N is applied to the car, how far will the car travel before it stops?

**physics**

If 335 g of water at 65.5 °C loses 9750 J of heat, what is the final temperature of the water? Liquid water has a specific heat of 4.18 J/(g.°C). °C (Answer a number only, no units. Round to the tenth place). This is an example of an endothermic or exothermic reaction?

**physics**

if some of water in calorimeter splash out when tranfering the metal block, will it affect the experiment result?

**Physics**

A plutonium- 239 nucleus initially at rest undergoes alpha decay to produce a uranium-235 nucleus. The uranium-235 nucleus has a mass of 3.90 x 10^-25 kg and moves away with a speed of 2.62 x 10^5 m/s. Determine the minimum wage electric potential difference that is required ...

**Physics**

A plutonium- 239 nucleus initially at rest undergoes alpha decay to produce a uranium-235 nucleus. The uranium-235 nucleus has a mass of 3.90 x 10^-25 kg and moves away with a speed of 2.62 x 10^5 m/s. Determine the minimum wage electric potential difference that is required ...

**physics**

A person is running from a cliff into a pond. The cliff has a height of 10.0m above the water but it is not strictly vertical, it slopes down to the pond at an angle of 40 degrees with respect to the vertical. What is the minimum speed the person needs to jump from the cliff ...

**physics**

An object is launched at an angle of 78º above the horizontal with an initial speed of 120 m/s. Find (a) the maximum altitude reached by the object, (b) its total time of flight, and (c) its horizontal range

**physics**

a 0.5 kg ball is thrown upward with an iniatial speed of 10 m/s, what is the initial kinetic energy of the ball and the total mechanical energy assuming initial potential energy is zero.

**physics**

Calculate the tension in a vertical strand of spider web if a spider of mass 8.00Ãƒâ€”10Ã¢Ë†â€™5 kg hangs motionless on it. (b) Calculate the tension in a horizontal strand of spider web if the same spider sits motionless in the middle of it much like the ...

**Physics**

a) A 40 cm radius wheel is rotating at 20rad/sec. How fast is this wheel moving across the ground? b) How far (in meters) will this wheel move in 6 seconds?

**Physics**

a) Find the angular velocity of a wheel that rotates 6 times every 4 seconds. b) What is the tangential velocity of the outside of the wheel if the radius is 15 cm?

**Physics**

In what part of the electromagnetic spectrum does the wavelength 0.0141 nanometers belong in?

**Physics**

a) Find the angular velocity of a 40 cm radius wheel that is moving at 20 m/s. b) How many times will this wheel rotate in 5 seconds?

**Physics**

A ball is thrown horizontally from the roof of a building 45cm tall and lands 24.0m from the base. What was the ball's initial velocity?

**physics**

Machines A, B, and C do the same amount of work, but they each take a different amount of time. Machine A takes more time as compared to machine C. Machine B takes the maximum time to do the same amount of work. Which machine expends the most power doing this work?

**Physics**

If a wheel revolving at 1800 r.p.m. slows down uniformly to 1200 r.p.m. in 25s, calculate the angular acceleration of the wheel and the number of revolutions it makes in this time.

**Physics**

Three equal charge Q each are place in the vertices of an equilateral triangle of side a.What is the resultant force on any one charge due to the other two?

**PHYSICS**

10N force applied at an angle of 30 degrees with the horizontal, find its horizontal component

**Physics**

A charge q is placed at h distance from the base of centre . Find the flux ?

**Physics**

A positive ion moves at a velocity of 2.4x10^5 ms in a circular path of radius 1.8m when a magnetic field of 0.315 T is applied. Find the mass of the ion. Assume a single charge.

**Physics**

Two parallel wires separated by 16 cm are carrying currents of 14 A (left) and 20A (right) in the same direction (up the page). Determine the magnetic field at position 3 cm to the right of the 20A wire. Calculate the distance where the magnetic field would be zero.

**Physics**

A particle, travelling at 5.2x10^3 ms, with a charge of 1.6uC, is moving up the page. It is at right angles to a magnetic field of 6.4 T in the direction of right. What is the magnitude and direction of the force on the particle?

**Science physics**

mandy drops a 2.0kg book from a height of 4.5m. how much work has gravity done on the book? M=2.0kg D= 4.5m Not actually sure what to do next. Because none of the formulas work. I need work but I don't even know the force. To find force I need mass which I have but I don't ...

**physics**

a tennis ball of mass 20g is released from rest at a height of 4m above the ground. on hitting the ground,it raises to a height of 3m.find the velocity with which it hits the ground.

**Physics**

If a sound has a wavelength of 3 m, what is its frequency? Use 340 m/s for its speed of sound.

**Physics**

3. Consider a freely falling object. a. What is the acceleration (in m/s2) after 5 seconds of fall? b. What is the acceleration (in m/s2) after 10 seconds of fall? c. What is the velocity (in m/s) after 5 seconds of fall? d. What is the velocity (in m/s) of 10 seconds of fall?

**Physics**

Suppose you are provided with 500 dice.calculate the number of throws that is equivalent to one half life and the decay costant for the process.under radioactivity decay analogue experiment

**Physics**

The Little Prince is a fictional character who lives on a very small planet as shown in the figure below. Suppose that the planet has a mass of 1.95 1013 kg and a radius of 1.06 103 m. (a) How long would it take for an object to fall from rest a vertical distance of 1.16 m? (b...

**physics**

Someone drops a ball from the roof of your building.The ball drop past your window. It takes time T to pass the window's height. What is the initial speed of the ball when it first came in view?

**Physics**

If you are casting a shadow of a ball on the wall, how do you make the umbra larger than the ball or is it impossible. Also, how can you make the umbra smaller than the ball or is it impossible? How can you make the radius of the penumbra larger than the balls radius? How can ...

**physics**

A object weighing 0.6netron is hung for an spiral spring and causes it to extend by 6.0cm the object is removed and a block of wood replacing it causes the spring to extermely 10.0cm what is the weight of the block of wood

**physics**

A sandal is dropped from the top of a 15.0-m-high mast on a ship moving at 1.75 m/s due south. Calculate the velocity of the sandal when it hits the deck of the ship: (a) relative to the ship and (b) relative to a stationary observer on shore. (c) Discuss how the answers give ...

**Physics**

A body is moving with uniform acceleration covers 100m in the first 10s and 150m in the next 10s. Find the initial velocity of the body.

**College Physics**

What mass can a 20000 watss engine pull at a speed of 30 m/s. If coefficient of friction is 0.15 between the mass and ground?

**Physics**

A train moving with constant speed of 54kmph moves eastwards for 30min then north for 40min find avg velocity

**Physics**

The Black Pearl has once again sailed into Port Royal and is firing its guns at the fort. The cannons atop the fort wall have been disabled, but there remains a single cannon at sea level which must defend the town. If the gunner estimates that the ship is 400 meters ...

**PHYSICS**

Why does the lower body rotate in the opposite direction when the upper body is thrown? angular momentum?

**PHYSICS**

A 5 kg block rests on a frictionless horizontal surface. A cord attached to the block passes over the pulley whose diameter is 0.120 m to the hanging block of mass 5 kg. The system is released from rest and the blocks are observed to move 3m in 2.0 s. A. What is the tension in...

**PHYSICS**

A string is wrapped around the rim of a flywheel 0.400 m in radius, and a steady pull of 50.0 N is exerted on the cord. The wheel is mounted in frictionless bearings on a horizontal shaft through it's center. The moment of inertia of the wheel is 4.00 kg.m^2 .Calculate the ...

**physics**

Determine the frequency of the note F4, 5 Seminotes above middle c (C4=261.6Hz) So would it be C4 = 261.6Hz x 1.05946^5 The fact they say semi notes is throwing me off, so I'm not sure if it's right.

**physics**

Red light with a wavelength of 7.0x10^-7 m travels at a speed of c. When it enters glass it's speed is reduced to 2.0x10^8 m/s. Calculate the wavelength of this redlight in glass. Assume that the frequency does not change. I'm really confused and I'm not sure how to do this ...

**Physics**

An air column that is open at both ends is 1.50m long. A specific frequency is heard resonating from the column what is the longest wavelength and it's associated frequency that could be responsible for this resonance? The speed of sound is 345m/s. So what I did is: v=2L = 2*1...

**PHYSICS, help!**

A 5 kg block rests on a frictionless horizontal surface. A cord attached to the block passes over the pulley whose diameter is 0.120 m to the hanging block of mass 5 kg. The system is released from rest and the blocks are observed to move 3m in 2.0 s. A. What is the tension in...

**Physics**

The left face of a biconvex lens has a radius of curvature of magnitude 12.8 cm, and the right face has a radius of curvature of magnitude 17.9 cm. The index of refraction of the glass is 1.45 a) Calculate the focal length of the lens for light incident from the left. b) After...

**Physics**

A roller coaster car is loaded with passengers and has a mass of 500 kg along with a speed of 18 meters/second at the dip. The radius of curvature of the track at the bottom point of the dip is 12 meters (gravity = 9.8 meters/second2). What force is exerted on the roller ...

**Physics help pls**

A spherical bowling ball radius 0.1 m and mass4.0 kg is rolling without slipping to ward the ball rack assume h=0.45m the liners sped at the bottom of the step is 2.85 m/s A find moment of interia of the ball B find the total kinetic energy st the bottom of step C find the ...

**PHYSICS**

A cord can b streated to it elastic limit by 2N.if a 35m of d cord by 0.6 By a force of 0.5n wat wil b d L wendforce2.5n

**physics**

A tennis ball with a velocity of 30.0 m/s to the right is thrown perpendicularly at a wall. After striking the wall, the ball rebounds in the opposite direction with a velocity of -8 m/s to the left. If the ball is in contact with the wall for 0.010 s, what is the average ...

**Physics 11**

A rifle bullet of mass 60g leaves the muzzle of a rifle with a V=5.8*10^2m/s. If the rifle has a mass of 3.1 kg, with what V will it recoil? I'm at a total loss here because I feel like I don't have enough information... I just need to know what formulas to use with the ...

**physics**

A hose contains 20 lamps of 200 W for each lamp and a heater of power 1500 W. they are all connected to supply voltage of 240 volt. Calculate; (a) The total current when all loads operates at the same time. (b) Total energy when 10 lamps and the heater they operate for 5 hours.

**physics 1**

a simple pendulum is 1m long.what is its period?

**physics 1**

what is the peiod of vibrating object which an acceleration of 8.0m/s .when its displacement is 1.0m?what should be the answer?

**physics 1**

a simple pendulum is used to measured the value of g.when the lenght of the pendulum is 98.5cm, the period is measured to be 2s.Find the value of g?

**physics**

A fighter jet is flying at Mach 3.2 in air of temperature 2 degrees C. What is the planes speed? I really don't understand how to do this question. I'd appreciate your help!

**Physics**

A seagull drops a claim from a height of 40m above the rocks. If the air temperature is 0 degrees C, how long after the claim is dropped does the sound of it drinking the rocks directly below reach the seagull? Assume that the seagull hovered in place during the drop.. So what...

**physics 1**

what is the peiod of vibrating object which an acceleration of 8.0m/s .when its displacement is 1.0m?what should be the answer?

**physics**

a destroyer sends out a sonar pulse that returns from a submarine in 1.68s. if the spped of sound in the sea of water is 1531m/s, how far away is the submarine I don't really understand what the question is asking. I appreciate your help! Thank you

**Physics**

10gm of steam 100°c are blown on the surface of 90gm water at 0°c contained in a calorimeter of water 10gm.all steams are condensed .calculate the increase in entropy of the system

**physics**

Does the momentum from the arms transfer to the body if you stop it when jumping? so if you jump vertically and you swing your arms forward to give them an angular momentum and then your arms reaches it's limit. does the angular momentum transfer to the body as a whole causing...

**physics**

Radon 86222Rn is a radioactive gas with a half-life of 3.82 d. If there are initially 400 decays/s in a sample, how many radon nuclei are left after 2 d ? Please help, I don't understand how to do this.

**science (physics)**

A body travels 10m in 5th second and 30m in 10th second. Find its initial velocity and acceleration.

**PHYSICS**

V R 5, L 1.2KG, HEIGHT 10M WORK INPUT 800J FIND THE USEFUL OUTPUT, EFFICIENCY, M A (TAKE G=10M/S )?

**PHYSICS**

A MACHINE HAS A VELOCITY RATIO OF 5 HAS AN EFFICIENCY OF 40.WHAT EFFORT WOULD BE NEEDED TO LIFT A LOAD OF 100N?

**Physics**

A 3-kg mass has a speed of 5.0m/s at the bottom of a 37 degree incline. How far up the incline does the mass slide before it stops if the friction force acting upon its motion is 20N? Thanks.

**Physics/ electricity**

Two charges, separated by a distance of 1.3 m, attract each other with a force of 0.078 N. If one charge is +3.7 μC, what is the other charge?

**Physics**

an earth satellite has an elliptical orbit with an eccentricity value, e=0.40 and on orbital period of 10 hours and 54.0 minutes. Find the height above the surface at its closest approach point.

**physics**

When a guitar string is sounded against a 440Hz note, 12 beats are heard in 2.0s. a) what are the possible frequencies of the string? b) when the same string is sounded against a 435Hz note, 33 beats are heard in 3.0s. What is the frequency of the string? I honestly am very ...

**physics**

how do i find maximum height (meters) and initial velocity (m/s) if i have the time (seconds), horizontal range, and horizontal velocity

**physics**

how do i find the horizontal velocity (m/s) when i have the angle, the time, and horizontal range?

**Physics HELP!**

A locomotive of mass 2.1 x 104 kg travelling at 2.0 m/s runs into an identical stationary locomotive. a) If the collision is perfectly inelastic, what is the speed of the two trains after the collision? b) If the collision is perfectly inelastic, what fraction of the energy is...

**Physics**

A 10.0 kg box is placed on a ramp that is inclined at 30.0 degrees to the horizontal. Determine the force of friction required to keep the block stationary. Determine the minimum coefficient of friction required to keep the box stationary.

**Physics**

A 12.0 kg object is on a surface that is inclined 30 degrees and the coefficient of friction is 0.65. Determine the force of static friction if the block remains stationary.

**Physics**

A 5.0 kg penguin sits on top of a 12 kg sled, as in the figure. A horizontal force of 45 N is applied to the sled, but the penguin keeps himself stationary by holding onto a string attached to the wall. The coefficient of kinetic friction between the penguin and the sled is 0....

**Physics**

On takeoff, the combined action of the engines and the wings of an airplane exert a force of 8.00 x 103 N on the plane upward at an angle of 65.0˚ above the horizontal. The plane rises with constant velocity in the vertical direction while continuing to accelerate in the ...

**Physics**

An 1800 kg helicopter rises with an upward acceleration of 2.0 m/s2. What lifting force is supplied by its rotating blades?

**Physics**

A baseball has a mass of 0.145 kilograms, and a bowling ball has a mass of 6.8 kilograms. What is the gravitational force between them if their centers are 0.5 m apart? 1.0 × 10–13 m 1.3 × 10–10 m 2.6 × 10–10 m 1.1 × 10–8 m

**physics**

a volumetric flask made of pyrex is calibrated at 20°c. if it is filled to 100ml with 35°c acetone. what us the volume of the acetone when it cools to 20°c and how significant is the change in the volume of the flask.

**physics**

A car is moving at 20 m / s before it applies the brakes for 4 s. It slows at a constant rate to 10 m / s. Five seconds after this, the brakes are applied again and stop the car in 5 seconds. The car slows at a constant rate during this period of time as well. What is ...

**Physics**

two basketball players collide player 1 with a mass of 55.0 kg experiences a -15.6 m/s2 acceleration. if the player 2 has a mass of 48.5 kg what acceleration did he experience immediately following the collision?

**11 grade / physics**

find the work by a body which is moving with a velocity of 10m/s and after covering some distance it has the velocity of 20m/s mass of the body 100kg

**Physics**

1. What happens to the stack of books if the applied force exceeds the maximum static frictional force? 2. What is the minimum size for the static frictional force, and under what conditions will the minimum static frictional force be observed? 3. What type of friction acts ...

**physics**

a force of 0.8N stretches an elastic spring by 2cm. find the force constant. f e = k=? f=ke 0.8=0.02 * k k=0.8/0.02 k=40N/m

**Physics**

a 10.0 kg box is placed on a ramp that is inclined at 30.0 degrees to the horizontal. Determine the force friction required to keep the block stationary. Determine the minimum coefficient of friction required to keep the box stationary.

**Physics**

A 12.0 kg object is on a surface that is inclined 30 degrees and the coefficient of friction is 0.65. Determine the force of static friction if the block remains stationary.

**physics**

what is the physics principle behind fiber optics

**Physics**

a charge q1=5.00nc is placed at the origin of an xy-coordinate system ,and a charge q2=-2.00nc is placed on the positive x-axis at x=4.00cm (a.) if a third charge q3=6.00nc is now placed at the point x=4cm, y=3.00cm. find the x and y components of the total force exerted on ...

**Physics-Answer Check**

You have an LED bulb that uses 4 watts of power and gives an output of 170 lumens. The operating voltage is 120 volts. Using this data, find the following. 1. What is the current that the LED bulb uses? Ans. 0.03 ampere 2. What is the effective resistance of this bulb? I'm not...

**Physics-Circuits**

How does a circuit breaker work to protect against an overloaded circuit?

**Physics**

A diver springs upward with an initial speed of 2.93 m/s from a 3.0-m board. (a) Find the velocity with which he strikes the water. [Hint: When the diver reaches the water, his displacement is y = -3.0 m (measured from the board), assuming that the downward direction is chosen...

**physics**

A rescue plane is flying horizontally at a height of 132 m above the ground. The pilot spots a survivor and releases an emergency kit with a parachute. The kit descends at a constant vertical acceleration of -6.89 m/s2 and the initial plane horizontal speed is 68.9 m/s. ...

**physics**

a car moves north with a constant velocity of 50km/hr.how far will it have traveeled in 4hours?the return trip takes 8hours. what is the average speed for the entire trip?

**Physics**

No idea how to do this. All I know is E=hf and found that a is 3.96 x 10^-19 Consider a sidewalk section that has an area of 1 m^2 and assume the sun is directly overhead. Also, assuming the sun is beaming primarily green light, which has a wavelength of 500 nm. (a) What ...

**Physics**

For a I got 36666.67 seconds which I don't know if its right and then b I know my answer is wrong because I got 0.0375 for wavelength.And I don't understand how to do e or f. The Voyager 1 spacecraft is at the edge of the solar system, about 11 billion km away. (a) How ...

**Physics**

When table salt is put in a candle ﬂame, it burns bright yellow because of emission from the sodium atoms. This emission is at 590 nm. (a) What is the natural resonant frequency of the sodium atom that produces this emission (i.e. what is the frequency of this light)? (b...