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Work Done on a Cart

A 70 kg cart is pushed 50m with a constant velocity upon a 45 degree frictionless incline. Find the work done on the cart (assume 10 m/s^2 gor gravity). Express in scientific notation and in joules.

Work and Energy - Force of Friction and Kinetic Friction

Question: A box of mass m = 20.0 kg is pushed at a constant speed of v = 2.5 m/s, and by a force F = 25.0 N along the horizontal plane. Show the algebraic steps: a) What is the force of friction between the box and the surface? b) What is the value of the coefficient of kinetic friction?

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 of Dropping a Book

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

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. See the attached file.

Spring Constant of the Spring

A 1200 kg car rolling on a horizontal surface has speed v = 66 km/h when it strikes a horizontal coiled spring and is brought to rest in a distance of 3.3 m. What is the spring constant of the spring?

Work & Energy - Average Force of Air Resistance

A softball having a mass of 0.25 kg is pitched at 114 km/h. By the time it reaches the plate, it may have slowed by 10 percent. Neglecting gravity, estimate the average force of air resistance during a pitch, if the distance between the plate and the pitcher is about 15 m.

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 (Force - Catapult)

A 20,000 kg jet takes off from an aircraft carrier via a catapult. The jet's engines exert a constant force of 136 kN on the jet. The force exerted on the jet by the catapult is plotted in Fig. 7-24b (see attachment) with F1 = 1200 kN and F2 = 73 kN. (a) Determine the work done on the jet by its engines during the launch of th

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

Heat and work

From what height one would have to drop a block of ice so that the energy obtained would be enough to melt the block and raise the temp of the water to 50 C.

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.

Work Energy and Velocity

A) Find the power input of a force F acting on a particle that moves with a velocity V for F=(6N)i - (5N)j and v = (-5 m/s)i + (4 m/s)j B) What is the angle between them?

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

Average Power P_avg Created by Force F

A sled of mass m is being pulled horizontally by a constant upward force of magnitude F that makes an angle theta with the direction of motion. The coefficient of kinetic friction is mu_k. The average velocity of the sled is v_avg. Find the average power P_avg created by force F. Express your answer in terms of F, theta, a

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