Tutorial Ques - Work done by forces - Questions to practice on Gravitational Potential energy, PDF

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Work done by forces - Questions to practice on Gravitational Potential energy, mechanical energy, kinetic energy and forces...

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Tutorial W eek 3 Section 6.1 W ork D one by a Constant Force Problem 6.1 During a tug-of-war, team A pulls on team B by applying a force of 1100 N to the rope between them. The rope remains parallel to the ground. How much work does team A do if they pull team B toward them a distance of 2.0 m?

Problem 6.2 You are moving into an apartment and take the elevator to the 6th floor. Suppose your weight is 685 N and that of your belongings is 915 N. (a) Determine the work done by the elevator in lifting you and your belongings up to the 6th floor (15.2 m) at a constant velocity. (b) How much work does the elevator do on you alone (without belongings) on the downward trip, which is also made at a constant velocity?

Problem 6.8 A person pulls a toboggan for a distance of 35.0 m along the snow with a rope directed 25.0 ° above the snow. The tension in the rope is 94.0 N. (a) How much work is done on the toboggan by the tension force? (b) How much work is done if the same tension is directed parallel to the snow?

Section 6.2 T he W ork-Energy Theorem and Kinetic Energy Problem 6.14 A golf club strikes a 0.045-kg golf ball in order to launch it from the tee. For simplicity, assume that the average net force applied to the ball acts parallel to the ball’s motion, has a magnitude of 6800 N, and is in contact with the ball for a distance of 0.010 m. With what speed does the ball leave the club?

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Section 6.3 Gravitational Potential Energy Problem 6.32 A pole-vaulter just clears the bar at 5.80 m and falls back to the ground. The change in the vaulter’s potential energy during the fall is -3.70´ 103 J. What is his weight?

Section 6.5 T he Conservaion of Mechanical Energy Problem 6.36 A 35-kg girl is bouncing on a trampoline. During a certain interval after she leaves the surface of the trampoline, her kinetic energy decreases to 210 J from 440 J. How high does she rise during this interval? Neglect air resistance.

Problem 4.12 The skateboarder in the drawing starts down the left side of the ramp with an initial speed of 5.4 m/s. Neglect nonconservative forces, such as friction and air resistance, and find the height h of the highest point reached by the skateboarder on the right side of the ramp.

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