King Fahd University of Petroleum & Minerals
Department of Physics

Quiz 4

Name:________________________________________ 		 Id #:____________

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Q:	Consider a constant force F = 60N acting on an object of  mass m = 10 kg and directed 30 degrees above the horizontal if the object starts with a speed of  4 m/s  from the initial point A.  

a)	Find the work done by the force F in moving the object a distance of 10 m from A to B along the horizontal surface.

b)	Find the speed of the mass m at point B if mk = 0.5 

King Fahd University of Petroleum & Minerals
Department of Physics

Quiz 4

Name:________________________________________ 		 Id #:____________

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Q:	Consider a mass m = 1 kg at height h = 1 m on the top of an incline with q = 30o. If the mass starts from rest at A and moves down all along the incline to reach point B, find :

a)	The work done by gravity from A to B.

b)	The final velocity at the bottom of the incline if mk = 0.2 .

King Fahd University of Petroleum & Minerals
Department of Physics

Quiz 4

Name:________________________________________ 			 Id #:____________

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Q:	A cord is used to lift vertically an initially stationary mass M = 100 kg to a height 10 m.

a)	What is the work done by gravity on the mass M during the lift.

b)	If the mass is lifted with a constant acceleration a = g / 2 find the work done
by the tension ( g = 9.8 m/s**2 ).

King Fahd University of Petroleum & Minerals
Department of Physics

Quiz 4

Name:________________________________________ 		 Id #:____________

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Q:	Consider a single force F = 2 x2 ( x is in m and F in N) acting on a particle with mass m = 1 kg where x is the position of the mass along the x-axis. If the mass starts with a speed of 4 m/s at x = 0.  

c)	Find the total work done by this force in moving the mass from x = 0 to x = 4 m .

d)	Find the final speed of the mass m at x = 4 m.