Unit: mechanics
Year: 1996 Question#: 16
Question: A horizontal force is used to pull a 5.0-kilogram cart at a constant speed of 5.0 meters per second across the floor, as shown in the diagram.
If the force of friction between the carts and the floor is 10. newtons, the magnitude of the horizontal force along the handle of the cart is
(1 ) 5.0 N
(2 ) 10. N
(3 ) 25 N
(4 ) 50. N
What is this question really asking?
Explanation by: Becky G
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Answer 1
5.0 N
INCORRECT
5.0 newtons would only be half of the magnitude of the horizontal force needed since if the frictional force is 10 N. Remember, constant velocity means Fnet = 0.
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Answer 2
10. N
CORRECT
If the speed is constant then all the info except the frictional force is unessasary and if the frictional force is 10 newtons, then the magnitude of the horizontal force is 10 N also. Remember, constant velocity means Fnet = 0. return to top
Answer 3
25 N
INCORRECT
the magnitude of the horizontal force along the handle of the cart is not 25N. Remember, constant velocity means Fnet = 0. return to top
Answer 4
50. N
INCORRECT
the magnitude of the horizontal force along the handle of the cart is not 50N. Remember, constant velocity means Fnet = 0. return to top
What's this question really asking?
How does the applied force compare to the force of friction if the object has a constant velocity? return to top
