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Work Energy Theorem

If the work required to speed a car up from 1.0 m/s to 4.0 m/s is 6000J, what is the mass of the car? How much additional work would be required to increase its speed from 4.0 m/s to 10.0 m/s?

Work and Energy

A boy pushes a lawn mower on a level lawn with a constant force of 540N at an angle of 30 degrees to the horizontal. Show the algebraic steps. How far does the boy push the mower in 2500J of work?

Work and Force

A spring with spring constant k= 1550 N/m is compressed by 0.020m, specify magnitude and direction algebraically: a) What force is required to do this? b) How much work is done in compressing the spring? c) What is the potential energy stored in the spring?

Word and Energy

A student lifts a book of mass 1.12 kg to a height of 1.24 m; use g=9.8 m/s^2, write an equation then calculate: a) How much work does the student do? b) What is the potential energy of the book? c) If the student drops the book vertically, what is the book's kinetic energy when it reaches the floor? d) What is the spe

Force and Motion

A car of mass 2500kg accelerates at 4.10 m/s^2 for 402. m: a) Calculate the work done by the net applied force in algebraic steps. b) What is its speed at the end of the drag race?

Simple Physics

A 615 kg car was involved in an accident. The accepted coefficient of friction between concrete and rubber is 0.65. The skid marks left by the car are 18.6m long. How was was the car moving when it hit the brakes?

Work and Energy Required to Stretch a Spring

A spring has k = 88 N/m. Draw a graph like that in Fig. 7-12 (see attachment). Use the graph to determine the work needed to stretch the spring from x = 4.4 cm to x = 6.6 cm, where x = 0 refers to the spring's unstretched length.

Work & Energy - Average Force Exerted

A baseball (m = 145 g) traveling 55 m/s moves a fielder's glove backward 35 cm when the ball is caught. What was the average force exerted by the ball on the glove?

Work and Energy

If the work required to speed a car up from 10 km/h to 20 km/h is 5.0 x 10^3 J, what would be the work required to increase the car's speed from 20 km/h to 30 km/h?

Mechanics: Work done against friction

The problem is: The light horizontal spring has a force constant of k=100 N/m. A 2.00 kg block is pressed against one end of the spring (compressing it 0.100 m). The block is released and moves from rest 0.250 m to the right of the release position. Show that the coefficient of kinetic friction between the block and the horizont

Easy EPE Problem

An electron and a proton are initially very far apart (effectively an infinite distance apart). They are then brought together to form a hydrogen atom, in which the electron orbits the proton at an average distance of 5.41 x 10-11m. What is EPEfinal - EPEinitial, which is the change in the electric potential energy?

The Continuity Equation

Petroleum flows along a 10-cm diameter pipeline at a speed of 2.0 m/s. Determine the flow rate, assuming the liquid is ideal.

A Cart Pulled Up an Incline

Consider a cart being pulled up at incline at a constant velocity. a) Will the work done be different for the following two positions of the force probe: parallel to the surface of the incline and at a 45 degree angle to the surface? Explain. b) Does the starting point, mass of the cart, or angle of inclination of the surface

A Cart on an Inclined Plane

A cart is on an inclined plane. If it is given a push up the ramp and released, then it moves up, reverses direction, and comes back down again. How will the kinetic energy change? How will the gravitational potential energy change? How will the mechanical energy change?

The Bermuda Triangle

Please do not place your response in a .pdf or .cdx format, but Word documents are okay. Thanks! Here's the actual problem: A cylinder with initial volume V contains a sample of gas at pressure p. The gas is heated in such a way that its pressure is directly proportional to its volume. After the gas reaches the volume 3V a

Problem 19.54

Please do not place your response in a .pdf or .cdx format, but Word documents are okay. Thanks! What is the power output of the engine? Please see attached for actual problem.

Work at Lifting and Lowering Phase

A weight lifter is bench-pressing a barbell whose mass is 85 kg. He raises the barbell a distance of 0.65m above his chest and then lowers the barbell the same distance. The weight is raised and lowered at a constant velocity. Determine the work done by the weight lifter during (a) the lifting phase and (b) the lowering phase

Power Output of a Motor

The crate has a mass of 150 kg and rests on a surface for which the coefficients of static and kinetic friction are us= 0.3 and uk = 0.2 respectively. If the motor supplies a cable force of F = (8t^2 + 20) N, where t is in seconds, determine the power output developed by the motor when t= 5s.

Kinetic Energy and Work

A 6.0 kg block is pushed 8.0 m up a rough 37 degree inclined plane by a horizontal force of 75N. If the initial speed of the block is 2.2m/s up the plane and a constant kinetic friction force of 25N opposes the motion, calculate the initial kinetic energy of the block, the work done by the 75N force, the work done by the frictio

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

How much work is done?

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

Mechanical Work

1. You and your roommate are dragging an exercise machine (mass 58.9 kg) down a 73.4 meter long hall, from the stair landing, where (because of union rules) the UPS driver left it, to your dorm room. The coefficient of friction with the floor is u = 0.917. a) The mechanical work you do in the process is how many kJ? b) Ass

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

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