21. A 0.600-kg particle has a speed of 2.00 m/s at point A and V kinetic energy of 7.50 J at point . What is (a) its kinetic energy at 0, (b) its speed at 6, and (c) the net work done on the particle by external forces as it moves from @ to (B? 22. A 4.00-kg particle is subject to a net force that varies with V position as shown in Figure P7.9. The particle starts from rest at x= 0. What is its speed at (a) x= 5.00 m, (b) x and (c) x = 10.0 m, 15.0 m?

9. AV R 6121W Higgins A.Nouvel onglet R 2634 W catalpa.. Physics 235-Spring 2023 Chapter 7 Worksheet The cable of a crane is lifting a 750 kg girder. The girder increases its speed from 0.25 m/s to 0.75 m/s in a distance of 3.5 m. a. How much work is done by gravity? b. How much work is done by tension?

A Net Force Fnet=(x-3x2)i + (2y2-y3)j acts on a 3.5 kg particle. a) Calculate the net work done on the particle as it moves from (1.0m,0.0m) to (1.0m,4.0m). b) At (x,y) = (1.0m,0.0m), the particle's speed is 5.0 m/s. Find the particle's speed at (x,y) = (1.0m,4.0m).

DIRECTION: CHOOSE THE CORRECT ANSWER F 1.A force of 5i+j+ 2k N displaced a body from a position of i+j+km to 2i +4j+ 6k m. How much work is done to displace it through this position? (A)18J (B)6J (C)12J (D)0J 2.Calculate the work done when a force of 2i+5j+ 5k N acts on a body when it produces a displacement of 2i + 4j+ 6k m. (A)54J (B)24J (C)50J (D)18J 3. A body of mass 10 kg at rest is acted upon simultaneously by two forces 4 N and 3 N at right angles to each other. The kinetic energy of the body at the end of 10 sec is (A)100 J (B) 300 J (D) 125 J 4) Consider an 80 kg man and 320 kg horse both running along a road with the same kinetic energy. (C)50 J The man must run (A) with the same speed as the horse. (CSS) 4 times as fast as the horse. (B) twice as fast as the horse. (D) 16 times as fast as the horse. 5)particle A is travelling at a velocity of []m/s. It collides with particle B which has a velocity of Jm/s. The particle move together. The mass of particle A is 2kg and the…

7. A student in a lab exerts a 25 N force to pull a block a distance of 48 cm. If a total of 11 J of work is done, the angle between the force and the displacement is a. 89° b. 66° d. 24° e. none of the above c. 61° 8. A 102-g sparrow flying at 12.3 m/s wishes to have equal kinetic and gravitational potential energies. The height that will accomplish this is a. 0.315 m b. 0.628 m d. 1.13 m e. 7.72 m c. 0.787 m 9. Earth's mass is 5.98 x 1024 kg. Calculate the value of g at a point 4.8 x 105 km from the centre of Earth. a. 9.8 × 102 N/kg b. 8.3 x 10' N/kg C. 1.7 × 103 N/kg d. 1.7 x 10³ N/kg e. 9.8 × 105 N/kg 10. A piece of paper becomes electrically charged when a charged rod of plastic is placed close to it. This is referred to as a. charging by a conductor b. charging by induction c. charging by an insulator A P d. charging by contact e. charging by electricity 20 cm Ꭰ T 20 cm 11. Four charged spheres, A, D, P, and T are arranged as shown below. Sphere A has a charge of +4.5 × 10*C,…

A 17 g bullet is accelerated in a rifle barrel81.5 cm long to a speed of 846 m/s.Use the work-energy theorem to find theaverage force exerted on the bullet while it isbeing accelerated.Answer in units of N.

1. A 4.0 kg particle is moving at a velocity v = V2î – V2ĵ + 3k m/s. (a) (b) What is the particle's kinetic energy at this moment? What is the net work done on the particle if its velocity changes to - V2î + 3k m/s? V = - Assume that a force in the x y plane acts on the particle to slow it down (imagine (c) that this force is a type of friction). Will the particle's kinetic energy become zero under the influence of this force? Explain your answer.

202.) The forces exerted by a rubber shock absorber varies with the displacement as shown. Estimate the work done to the ball shown after it has displaced the shock absorber 8.0 cm. Has the ball gained or lost energy? O Work Rubber Shock Absorber Force (Newtons) Clearly indicate how you make your estimate. Work 1.7NM Has the ball gained or lost energy? 40 30 20 10 4 8 10 Displacement (cm)

15. A particle is subject to a force F, that varies with posi- W tion as shown in Figure P7.15. Find the work done by the force on the particle as it moves (a) from x = 0 to 5.00 m, (b) from x = 5.00 m to x = 10.0 m, and (c) from x= 10.0 m to x = 15.0 m. (d) What is the total work done by the force over the distance x = 0 to x = 15.0 m? x= F, (N) 3 2 1 0 x (m) 2 4 6 8 10 12 14 16 Figure P7.15 Problems 15 and 34.

A 2.03 kg mass is initially at rest upon a horizontal surface. An applied force of 17.6 N i then acts on the object over a distance of 2.92 m. If the final velocity of the object is 4.09 m/s i, what is the work done by kinetic friction over that distance moved?