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Work, Power and Force.

Please do not put your response in a .pdf format, but Word documents are okay. Thanks! (A) A sled of mass m is being pulled horizontally by a constant horizontal force of magnitude F. The coefficient of kinetic friction is mu_k. During time interval t, the sled moves a distance s, starting from rest. Find the average power Pa

What is the total work done by the two tugboats on the supertanker?

Two tugboats pull a disabled supertanker. Each tug exerts a constant force of 1.9e10^6 N, one at an angle 12.0 degrees west of north, and the other at an angle 12.0 degrees east of north, as they pull the tanker a distance 0.700 km toward the north. What is the total work done by the two tugboats on the supertanker? Express your

Physics Calculations: Finding the Length of a Ramp

Question: Truck brakes can fail if they get too hot. In some mountainous areas, ramps of loose gravel are constructed to stop runaway trucks that have lost their brakes. The combination of a slight upward slope and a large coefficient of friction in the gravel brings the truck safely to a halt. Suppose a gravel ramp slopes upwar

Work done/Energy burnt using weight lifting

2.) Your new exercise machine involves lifting weights a standard height of 52.0 cm. a) How much work do you do if you lift 37.8 kg? (in J) Exercise requires a food input about four times your mechanical work output (in other words, about 25% efficiency). A "food calorie" is actually 1000 standard calories and a standard

Block on a incline AND energy

A block of weight mg sits on an inclined plane as shown. A force of magnitude F is applied to pull the block up the incline at constant speed. The coefficient of kinetic friction between the plane and the block is Mu. What is the total work done on the block by the force of friction as the block moves a distance L up the

Please, show me how you got the answers and give me the answers. Thanks

1. An overhead projector with a lens of 35.6-cm focal length is used to throw an image on a screen 1.80 m away. If you consider the lens to be a thin lens, how far is the slide from the lens when the image is in focus? What is the magnification in this setup? Work this problem by ray tracing? 2. Work Problem 1 using the thin-

Ups and Downs

(a) A ball is launched with initial speed v from ground level up a frictionless slope. The slope makes an angle theta with the horizontal. Using conservation of energy, find the maximum vertical height hmax to which the ball will climb. Express your answer in terms of v, g, and theta. You may or may not use all of these quantiti

Example Physics Problems

1. If there is a maximum frictional force between your shoe and the track, does that set a limit on how fast your can start (accelerate) in sprint? Does that mean you cannot have more than a certain acceleration even if your have increduly strong leg muscles? What is done to solve this problem? 2. Explain why friction is impo

Basic Physics (Tension; Displacement; Force etc.)

A 230kg crate hangs from the end of a rope of length L-12.0m. You push horizontally on the crate with a varying force F to move it distance d=4.00m to the side (see attached picture). (a) what is the magnitude of F when the crate is in this final position? During the crate's displacement, what are (b) the total work done on i

Kinetics Problems

A skier is pulled by a tow rope up a frictionless ski slope that makes an angel of 12 degree with the horizontal. The rope moves parallel to the slope with a constant speed of 1.0m/s. The force of the rope does 900J of work on the skier as the skier moves a distance of 8.0m up the incline. (a) If the rope moved with a constant s

Roller Coaster Physics

ROLLER COASTER DESIGN Designing a roler coaster is very tricky. Patrons of theme and amusement parks want to be thrilled , but generally do not want to be injured. Downard accelerations of greater than 10 g cause bodily harm. Negative (i.e upward) accelerations of greater than about 5 g also cause damage ( "red out") The

Distance Calculations of a Football Field

80. To go to a football stadium from your house, you first drive 1000 m north, then 500 m west, and finally 1500 m south. (a) Relative to your home, the football stadium is (1) north of west, (2) south of east, (3) north of east, or (4) south of west. (b) What is the straight-line distance from your house to the stadium? 8

Roller Coaster Work Problem

The questions refer to the roller coaster in the diagram (attached). The mass of the roller coaster, including passengers = 500 kg. Assume that friction and drag forces are so small they can be ignored. 1. Measured from "ground level," what is the gravitational potential energy of the roller coaster at the top of the first hi

Please, find the anwer and show me how you got it if you can

1>What is the electric potential at a point 0.45 m away from a point charge of a of 2.5mC 2> If 3.75 X 10^-4 J of work are required to move 13.7 microc of charge from one point to another, what is the electric potentail difference the two points. 3> An electron is released from rest in a vacumm between two flat, parallel

Micro-F Capacitor Voltages

Hi. Can someone please check these two answers? (a) seems very low and (b) seems very high to me. A 0.22 micro-F capacitor is charged by a 1.5-V battery. After being charged, the capacitor is connected to a small electric motor. Assuming 100% efficiency, (a) to what height can the motor lift a 5.0-g mass? (b) What initial vol

Fluids, Pressure and Depth

A patient is to receive an intravenous injection of medication. In order to work properly, the pressure of fluid containing the medication must be 109 kPa at the injection point. (a) If the fluid has a density of 1020 kg/m^3, find the height at which the bag of fluid must be suspended above the patient. Assume that the pressure

Energy of ejected electrons

A magnesium surface has a work function of 3.68 eV. Electromagnetic waves with a wavelength of 215 nm strike the surface and eject electrons. Find the maximum kinetic energy of the ejected electrons. Express your answer in electron volts.

Working with the center of mass of the Earth-Moon system

I've tried this one 3 times, and couldn't get the correct answer no matter what I tried, help! (a) How far is the center of mass of the Earth-Moon system from the center of the Earth? (Appendix C gives the masses of the Earth and the Moon and the distance between the two.) (b) Express the answer to (a) as a fraction of the E

Laws of Motion/Free Fall

Question: When baseball players throw the ball in from the outfield, they usually allow it to take one bounce before it reaches the infield, on the theory that the ball arrives sooner that way. Suppose that the angle at which a bounced ball leaves the ground is the same as the angle at which the outfielder threw it, but that the

Classical Physics Problems

1. During a rockslide, a 520 kg rock slides from rest down a hillside that is 500m long and 300m high. The coefficient of kinetic friction between the rock and the hill surface is 0.25 (a) If the gravitational potential energy U of the rock-Earth system is zero at the bottom of the hill, what is the value of U just before the

The Conservation of Energy

A skier coasts down a very smooth, 10-m-high slope (v =20 m/s), what is his speed at the bottom of the slope. If the skier has a mass of 60kg and the force of friction retards his motion by doing 2500 j of work, what is his speed at the bottom of the slope?

Spring constant problem: Work done, speed of block, maximum compression

A 230 g block is dropped onto a relaxed vertical spring that has a spring constant of k = 2.5 N/cm (Fig. 7-30). The block becomes attached to the spring and compresses the spring 14 cm before momentarily stopping. What work is done on the block by the spring force while the spring is being compressed? (in J) What is the s

Strength of a fishing line

1. The tension at which a fishing line snaps is commonly called the line's "strength." What minimum strength is needed for a line that is to stop a salmon of weight 85 N in 8.0 cm if the fish is initially drifting at 2.5 m/s? Assume a constant deceleration.

Point Charges

Two point charges each of magnitude 2.00 ìC are located on the x axis. One is at x = 1.00 m, and the other is at x = -1.00 m. (a) Determine the electric potential on the y axis at y = 0.500 m. (b) Calculate the change in electric potential energy of the system as a third charge of -3.00 ìC is brought from infinitely far

Throwing a stone off a bridge

A man standing on a bridge 30m above the water throws a stone in a horizontal direction. Knowing that the stone hits the water 40m from a point on the water directly below the man determine (a)the initial velocity of the stone (b)the distance at which the stone would hit the water if it were thrown with the same velocity from a

Two conducting wires each of length L are...

Two conducting wires each of length L are connected to a knob, whereby a total electric charge Q is deposited onto two small spherical metallic spheres, each of mass m and diameter d, at the end of the wires. We observe each wire of this electroscope to lie at an angle q from the vertical. Find an expression for the charge Q

Kinetic frictional force for a skier: Work done, magnitude of force

A 63 kg skier coasts up a snow-covered hill that makes an angle of 25 degrees with the horizontal. The initial speed of the skier is 6.6 m/s. After coasting a distance of 1.9 m up the slope, the speed of the skier is 4.4 m/s. (a) Find the work done by the kinetic frictional force that acts on the skis. (b) What is the magni

Energy Theorem and Kinetic Energy

A fighter jet is launched from an aircraft carrier with the aid of its own engines and a steam-powered catapult. The thrust of its engines is 2.3 x 10^5 N. In being launched from rest it moves through a distance of 87 m and has a kinetic energy of 4.5 x 10^7 J at lift-off. What is the work done on the jet by the catapult?