Practice 5A: | 1 | 2 | 3 | 4 | Go up
Work- By Krista Heim, 2001

1. A tugboat pulls a ship with a constant net horizontal force of 5.00x10^3 N and causes the ship to move through a harbor.  How much work is done on the ship if it moves a distance of 3.00 km?

Here's what you know, F=5.00x10^3 N, d=3000m, use the formula W = Fd, W=(5x10^3)(3000), solve for W, W=1.5x10^7 J.  
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2. A weight lifts a set of weights a vertical distance of 2.00 m.  If a constant net force of 350 N is exerted on the weights, what is the net work done on the weights? 

Here's what ya know, F=350 N, d=2.00m, use W = Fd, W=(350)(2.00), solve, W=700 J.  
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3. A shopper in a supermarket pushes a cart with a force of 35 N directed at an angle of 25 degrees downward from horizontal.  Find the work done by the shopper on the cart as the shopper moves along a 50.0 m length of aisle. 

Here's what you know, F=35 N, q=25degrees downward- which is actually -25 degrees, d=50.0m, use the formula W = Fd(cos q), W=35*50(cos -25), solve, W=1600 J.  

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4. If 2.0 J of work is done in raising a 180 g apple, how far is it lifted?

Here's what you know, W=2.0 J, m=.180 kg, first use the formula Fg = mg, Fg =(.180)(9.8), solve, Fg =1.764 N, now use the formula W = Fd, 2.0=1.764d, solve for d, d=1.1m.  
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