# Homework Help: Science: Physics

## Recent Homework Questions About Physics

**physics**

A stone of 400g is whirled by a string of length 2.8m so that it moves in horizontal circle of radius 0.7m.find the tension on the string.

**Physics**

Suppose that at least 14.7 eV is needed to free an electron from a particular element, i.e., to ionize the atom. What is the lowest frequency photon which can accomplish this? And, what is the corresponding wavelength for that photon?

**physics**

a curve along the highway is to be banked for traffic expected to move at 80km/hr. find the angle of banking if the radius of the curve is 100 meters

**Physics**

A water tank is 20 metre Doon Ek Baar water barometer is estimated that Palace then what is the pressure at the bottom of the tank in atmosphere

**Physics**

A water tank is20m deep if the water barometer reads10m at that place then what is the pressure at the bottom of the tank in atmosphere

**Physics**

A force F =(8.700 N)i +(−9.000 N)j F→=(8.700 N)i +(−9.000 N)j is exerted on a particle located at r=(−8.400 m)i +(7.700 m)j r→=(−8.400 m)i +(7.700 m)j. What is the torque on the particle about the origin?

**physics**

A boy has a mass 40kg and a girl of mass 30kg play on a see-saw, where must the girl sit to make it balance?

**physics**

A girl uses a spanner of length 20cm to tighten a nut. IF she pulls at right angles to the end of the spanner with a force of 50N, calculate the moment of her pull

**Physics**

How could you use 100 pounds of force to lift a 200 pound weight? Explain precisely, listing any necessary distances and details. (This will take some converting!) I don't understand this question, could someone please help me? I think I only need the distances from the ...

**Science Physics**

An air plane flies 20 km in a direction 60 degree west of north then 40 km straight east and then 10 km in a direction 30 degree north of east . How far and at what direction is the plane from the starting point?

**Physics**

How could you use 100 pounds of force to lift a 200 pound weight? Explain precisely, listing any necessary distances and details. (This will take some converting!) I don't understand this question, could someone please help me? I think I only need the distances from the ...

**Physics**

You are given five identical resistors each of resistance r. How can you arrange all these resistors (in series, in parallel, or both) in order to have an equivalent resistance of 7r/2, 7r/3 or 2r

**physics**

Find the gravitational force of attraction between two balls each weighing 10 kg,when placed at a distance of 1 meter apart

**physics**

Does the kinetic energy of a car change more when it speeds up from 10 to 15 m/s or from 15 to 20 m/s? Explain.

**physics**

Does the kinetic energy of a car change more when it speeds up from 10 to 15 m/s or from 15 to 20 m/s? Explain.

**Physics**

While analyzing a sample of one, geologist finds that it weighs 2n in air and 1.3N when immersed in water. Calculate the density of the one

**Physics**

A ball thrown downward with an initial velocity of 20m/s.what will be itsvelocity after 5s

**Physics**

A 5 gm bulet initial velocity is 300ms-1 and after penetrating a 5cm plank then the bulet stopped . So how much time is needed to penetrate the plank..?

**vertical motion physics**

a body projected vertically up from ground crosses a point Pafter 4 seconds and again after 6 seconds Maximum height reached by that body above the ground is (g=10m/s)

**physics**

Two forces are applied to a 0.5 kg hockey puck causing it to accelerate. The first force has a magnitude of 10.0 N and is applied to the puck at an angle of 80 degrees with respect to the x axis. The second force has a magnitude of 3.5 N and is applied to the puck at an angle ...

**Physics**

A 238U nucleus is moving in the x-direction at 5.0x10^5m/s when it decays into an alpha particle (4He) and a 234Th nucleus. The alpha moves at 1.4x10^7 m/s at 22 degrees above the x-axis. Find the recoil velocity of the thorium. I know that the original x momentum is 238*5.0*...

**Physics**

A 103kg SWAT team member descends a 27.5m cable attached to a helicopter. If he wishes to reach the bottom in 3.5s, what average force should he apply to the cable?

**Physics**

an upward force of 45.0N is applied to catch a falling girl's bowling ball with a mass of 5.45kg(12lb). What is the acceleration of the ball

**Physics**

Two identical loudspeakers are 2 m apart. A person stands 4.6 m from one speaker and 3.4 m from the other. What is the lowest frequency at which destructive interference will occur at this point?

**physics**

Specific heat capacity of a certain metal is found by heating the metal and then placing it into water which is in a container made of the same material. The metal has mass of 100g and is heated to 100 degrees celsius. The container has mass of 200g and contains water of 500g ...

**sir damon i need u help physics**

The equation y=As in(wt-kx)represents a plane wave traveling along the x-direction. If a=0.10m, w=8500hz and k=25/secs......Calculate the speed of the Waves -Calculate the speed of the medium through which the wave is travelingl -What is the equation of the reflected wave ...

**Physics**

A 12000 kg truck strikes the back end of a 750 kg car moving at 15 m/s. If the truck loses 7500 kg-m/s of its momentum to the car, what is the car's velocity after the collision? I'm not sure how to solve this one... Help please?!

**physics**

How many minutes would it take a radio wave to travel from the planet Venus to earth?

**physics**

A 1 meter long rod of diameter 1 cm supports a hanging mass of 10^4kg. The rod stretches by 6.2 mm. What is Young's modulus for the rod?

**physics need help anybody**

The equation y=As in(wt-kx)represents a plane wave traveling along the x-direction. If a=0.10m, w=8500hz and k=25/secs......Calculate the speed of the Waves -Calculate the speed of the medium through which the wave is travelingl -What is the equation of the reflected wave ...

**PHYSICS URGENT!!!**

Consider a solid ball of mass m = 50g and is placed on a long flat slope that makes an angle of 30° to the horizontal. The ball was initially at rest and was then released such that it rolled down the slope without slipping. With a detailed explanation of your method ...

**Physics**

A steel spring is hung vertically. Using a ruler, the lower end of the spring was measured to be 25.0cm from its upper end. However, when an object of mass 0.500kg it attracted to the lower end of the spring the spring stretches to a new length of 45.0cm. With the aid of a ...

**PHYSICS PLEASE HELP ME**

Consider a solid ball of mass m = 50g and is placed on a long flat slope that makes an angle of 30° to the horizontal. The ball was initially at rest and was then released such that it rolled down the slope without slipping. With a detailed explanation of your method ...

**Physics- Equilibrant Force**

Two movers are pushing a large crate with a force of 50.0 N each. One pushes north, the other east. What is the equilibrant force? a. 71 N Southwest b. 50 N Northeast c. 100 N Southeast d. 71 N Northeast

**Physics- Equilibrium**

Which of the following is in equilibrium? a. an object that was thrown straight upward at the moment it has zero velocity (my answer) b. an object moving in a circle at constant speed c. an object that moves at constant velocity d. an object that moves at constant acceleration

**Physics- Accleration of a Falling Penny**

A visitor to the observation deck of a skyscraper manages to drop a penny over the edge. As the penny falls faster, the force due to air resistance increases. How does this affect the acceleration of the penny? a. The acceleration decreases b. The acceleration remains constant...

**Physics**

Is it true that with buoyancy, the weight of the displaced water equals the weight of the complete object, even if only a part of the object is submerged? If so, why, since the weight of a larger object would be greater than that of a smaller one?

**Physics- Baseball thrown upwards, accleration**

When a baseball is thrown straight upward, what is its acceleration at its greatest height? a. 9.8 m/s2 upward b. 9.8 m/s2 downward (my answer?) c. 0 m/s2 d. 9.8 m/s2 horizontally

**Physics- Object Reaches Maximum Height**

When an object that has been thrown into the air reaches its maximum height, which is true? a. its velocity is zero. b. it is at its terminal velocity. c. it is not in free fall. d. its acceleration is zero.

**Physics-Tension Force**

A strong, weightless rope has a 0.15 kg mass hanging from the middle of it. What tension force will make the rope horizontal, corresponding to θ=0°?

**Physics**

A baseball with a mass of 0.145 kg is thrown straight down at the ground. At a particular speed, it has a drag force of 0.4 N acting on it. What is its acceleration at that time? a. -7.0 m/s2 b. -2.8 m/s2 c. -9.8 m/s2 d. -12.6 m/s2

**Physics**

Two spherical objects have masses of 3.5 x 10^7 kg and 6.5 x 10^9 kg. Their centers are separated by a distance of 125000 m. Find the gravitational attraction between them.

**Physics**

The temperature of the Sun’s surface (the so-called photosphere) is about 5500 C. Assume that the Sun’s surface is pretty close to a perfect black-body emitter. (a) At what wavelength does the peak intensity of Sun’s radiation lie? (b) Estimate the total power radiated ...

**physics**

A uniform rigid rod of mass 1kg and length 30cm. Find the moment of inertia of the rod about an axis perpendicular to the rod through on end.

**Physics**

A 51-kg vampire and 139-kg werewolf clash during the Feat of Strength part of the annual celebration of Festivus. The werewolf velocity just before the clash is 6 m/s and is directed upwards, while the vampire velocity at the moment of the collision is 10m/s and is directed ...

**Physics**

The electric field between two equally but oppositely charged parallel plates is 2.35 N/C [south]. If a charge of –2.00 C was placed at the midway point between the plates, what force (magnitude and direction) would act on the charge? Give the direction as acting north or ...

**physics**

(1) a car travelling at a constant speed of 20ms-1 overcomes a constant frictional resistance of 300N. What is the horse power of the engine? ( take 1h.p = 3/4 kw)

**Physics**

You row a boat perpendicular to the shore of a river that flows at 2.5 m/s. The velocity of your boat is 4.5 m/s relative to the water. (a) What is the velocity of your boat relative to the shore? (b) What is the component of your velocity parallel to the shore? (c) What is ...

**physics**

suppose the experiment was conducted on the surface of the moon of about 1-6th that of the earth. If a single period takes exactly 1.00 second, how long does a period take on the moon ?

**Physics**

A car travels at an average speed of 100k-m/hr what distance does it cover in 5min.hint speed=distance/time

**Physics**

In a vertical lifting an object with mass of 2kg is lifted 1m above the ground. A work of 80J is done with a constant force. What is the acceleration of the object?

**Physics**

A 0.14 kg baseball is pitched at a speed of 35 m/s. If it is hit straight back at the pitcher with a force of 5400N exerted over a time interval of 1.0 millisecond, find: the distance that the baseball was in contact with the bat (hint, use d = Vave*t) Vave = 1/2(vi + vf) Vave...

**Physics**

An astronaut lands on a distant planet and places a mathematical pendulum with a length of 50 cm. He measures that the pendulum makes 100 oscillations in 136 sec. What is the gravity acceleration on that planet.

**Physics**

Water drops from a waterfall 84 meters high .The temperature of the water at the bottom is found to be 26.2 degrees Celsius. Calculate its temperature at the top of the waterfall

**Physics**

A 1200 lb sleigh is pulled along a horizontal surface at uniform speed by means of a rope that makes an angle of 30 degrees above the horizontal. If the tension in the rope is 100 lb., what is the coefficient of friction?

**very hard PHYSICS QUESTION**

Consider a solid ball of mass m = 50g and is placed on a long flat slope that makes an angle of 30° to the horizontal. The ball was initially at rest and was then released such that it rolled down the slope without slipping. With a detailed explanation of your method ...

**Physics**

in air, an object weights 15N. when immersed in water, it weights 12N. when immersed in another liquid, its weights 13N. determine the density of the object, the relative density of the object and the density of the other liquid?

**Physics**

A wheel rotating initially at an angular velocity of 1.0 rad/s, accelerates over a 10 S interval at a rate of 0.1 rad/s^2. What angular displacement does the wheel undergo in this 10 S interval, in terms of revolutions?

**Physics**

A bullet traveling at 200 m/s strikes a soft wood and penetrates 4.5 cm through it before coming to rest. Calculate the bullet's average retardation

**Physics**

A 1 kg mass attached to a 1 m string is rolled around in a horizontal circular path with an angular velocity of 100 RPM what is the tension of the string? Please show how you got your answer.

**Physics**

Three boxes are lined up so that they are touching each other as shown in the figure below. Box A has a mass of 30.0 kg, box B has a mass of 45.0 kg, and box C has a mass of 75.0 kg. An external force (F) pushes on box A toward the right, and the force that box B exerts on box...

**physics**

A solar collector is placed in direct sunlight where it absorbs energy at the rate of 780 J/s for each square meter of its surface. The emissivity of the solar collector is e = 0.76. What equilibrium temperature does the collector reach? Assume that the only energy loss is due...

**physics**

A ball is projected with initial velocity 50m\s at an angle of elevation of 37°from the top of a cliff 55m high. calculate the total time the ball is in the air and the maximum horizontal distance covered...please I have solved this question but didn't get the answer ..I need...

**physics**

A skate boarder traveling at a constant speed of 22 m/s on a road comes to a straight incline with a constant slope (do not use g for incline). While going up the incline, the skater has constant deceleration. If she is 16m up the incline after 12.0 s A) what is the ...

**Physics**

A car is proceeding at a speed of 12.0 m/s when it collides with a stationary car in front. During the collision, the fist car moves a distance of 0.300 m as it comes to a stop. The driver is wearing her seat belt, so she remains in her seat during the collision. The driver’...

**physics**

What is the period (in seconds) of a simple pendulum 62.0 cm. long, on the earth?

**Physics**

A block that has a mass of 0.0190 kg and a block that has a mass of 2.00 kg are attached to the ends of a rope. A student holds the 2.00-kg block and lets the 0.0190-kg block hang below it; then he lets go. Air resistance can be neglected. 1)What is the tension in the rope ...

**physics**

A pendulum makes 27 vibrations in 36 s. What is its period in seconds?

**physics**

A fisherman's scale stretches 2.3 cm. when a 2.1 kg. fish hangs from it. What will be the frequency of vibration if the fish is pulled down and released so that it vibrates up and down?

**Physics**

A 35.1 g pinball starts at the top of a frictionless pinball table inclined at 46.0°. If the ball is released and the spring at the bottom is compressed 0.0600 m and has a spring constant of k = 27.7 N/m, how far back up the pinball table will the pinball travel before ...

**physics**

When a 85.0 kg. person climbs into an 1800 kg. car, the car's springs compress vertically 1.8 cm. What will be the frequency of vibration when the car hits a bump? (Ignore damping.)

**Physics**

An angle of a circle with a 2 m radius is delta theta = 20 degree. What is the corresponding arc length delta s?

**Physics**

The block of mass 3.43553 kg has an acceleration of 2.1 m/s^2 as shown. / / F a _____________ <-/ )23 degree <---- |_3.43553kg_| What is the magnitude of F? Assume the acceleration due to gravity is 9.8 m/s^2 and the surface is frictionless. Answer in units of N

**physics**

A water is operated by solar power. If the solar collector has an area of 5.25m2, and the intensity delivered by sunlight is 475W/m2, how long does it take to increase the temperature of .600m3 of water from 20.C to 85.0C?

**physics**

Two moles of an ideal gas have a volume of 3.43X10-3m3. the initial temperature of the gas is 78.0C. If the pressure is held constant while it is heated to a final temetatue of 275C, what would be the final volume?

**physics**

A .524kg object is tied down to the bottom of a container which container an unknown fluid. the tension in the rope is 38.5N. the object displaces .00735m3 of unknown fluid. Find the density of the unknown fluid.

**Physics**

A wheel is rotating with angular velocity 14 rev/s. What angular acceleration would be needed to bring the wheel to rest in a single rotation?

**physics**

Two forces are exerted on a hockey puck which initially stopped on frictionless ice. Force 1 is exerted in the positive x direction with magnitude of 10 N and Force 2 is exerted in the positive Y direction with magnitude 4 N. The hockey puck has a mass of 0.5 kg. What is the ...

**Physics**

0 degree centigrade temperature cause 300m/s2 how many centigrade temperature cause 400 m/s2 velocity

**Physics**

An electric heater supplied at 40 Volt's draws a current of 5 ampere. If it is now connected to a 120 Volt supply, find the value of current being drawn ?

**Physics**

A nichrome wire of diameter 5mm and length 5m has resistivity of 10^-4 ohm meter. If wire is compressed to double it's diameter. Find the resistance in its new form. Also find the resistance of the wire originally ?

**physics**

A uniform rod of 1 meter is bent at its midpoint to make90.The distance from its centre of mass

**physics**

If your car goes from 0 mi/h to 70 mi/h in 8 s, what is your average acceleration? Answer in units of miles/(hours x seconds ).

**physics**

One day while moving boxes you get tired and decide to use a rocket instead. You attach a small rocket of negligible mass to a 6.45 kg box. When you turn the rocket on, it provides a constant thrust of 212 N, and the sbox begins sliding across the pavement. If the magnitude of...

**physics**

A uniform plank AB which is 75m long and has a weight of 350N and is supported horizontally by two vertical ropes A and B. A weight of 100N rest on the plank at C where AC=4m. Find the tension in each rope A and B

**physics**

A girl uses a spanner of length 20cm to tighten a nut. If she pulls at right angles to the end of the spanner with a force of 50N,calculate the moment of her pull

**Physics**

A 3.20 kg block starts at rest and slides a distance d down a frictionless 30.0° incline, where it runs into a spring (Fig. 8-6). The block slides an additional 23.0 cm before it is brought to rest momentarily by compressing the spring, whose spring constant k is 443 N/m. Fig...

**Physics**

You demonstrate hitting a board in a karate class. The speed of your hand as it hits the thick board is 12 m/s with respect to the board, and the mass of your hand is about 0.74 kg. How deep does your hand go into the board before stopping if the collision lasts for 2.0×10−3s?

**Physics**

What role does the mass of the projectile play in changing the horizontal and vertical motions of the projectile? Why? Thank you!

**Physics**

A car with its passengers have a total mass of 4200kg .the car is travelling along a horizontal road when it moves ,it experiences a forward driving force of magnitude F newtons and a constant resistance force(opposite to driving force)of 850N a)what is the value of F if the ...

**Physics**

A beam of partially polarized light can be considered to be a mixture of polarized and unpolarized light. Suppose a beam of partially polarized light is sent through a polarizing filter. The polarization direction of the filter can be changed by rotating it. As the filter is ...

**Physics**

A wheel accelerates from rest to 59 rad/s at a rate of 58 rad/s^2 What is the angular displacement of the wheel??? A) 24 rad B) 38 rad C) 30 rad

**Physics**

A 3500kg truck moving at 45km/h collided head on with a 1600kg car moving at 25km/h. Find the velocity of the combined cars after the collision.

**Physics**

A pipe is open at both ends. The pipe has resonant frequencies of 655 Hz and 786 Hz (among others). Find the two lowest possible values for the length of the pipe. Use c = 343 m/s for the speed of sound. __ m __ m?

**physics**

A 6.95 kg bowling ball is dropped 2.20 m onto a large spring. If the bowling ball compresses the spring by 0.55 m, what must the spring constant of the spring be?

**physics**

A spring gun shoots out a plastic ball at speed v0. If the ball's speed is increased by a factor of 2, what distance must the spring have been compressed?

**Physics**

Calculate the kinetic energy that the earth has because of (a) its rotation about its own axis and (b) its motion around the sun. Assume that the earth is a uniform sphere and that its path around the sun is circular. For comparison, the total energy used in the United States ...

**Physics**

An object is sliding along a flat surface with an initial speed of 30 m/s. What must the coefficient of kinetic friction be between the object and the surface if the object slides to a stop in 10m? What would be the speed of the object after it had only slide half that distance?

**physics**

A mass of 8kg is whirled round in a vertical circle using a rope of length 80cm if it makes 2.5 cycles in 1 second, calculate the maximum tension the rope experiences

**Physics**

A 52 kg woman is standing in a 26 kg cart that is moving a velocity of 1.2 m/s S. The woman staying rest then moves at a velocity of 1m/s (E) what is the final velocity of the cart? I just ugh, don't even know how to even start answering the question as this deals with ...