Unit: Work and Energy
Year: 1992 Question#: 54
Question: As shown in the diagram below, pulling a 9.8-newton cart a distance of 0.50 meter along a plane inclined at 15 degrees requires 1.3 joules of work. If the cart were raised 0.50 meter vertically instead of being pulled along the inclined plane, the amount of work done would be:
(1 ) less
(2 ) greater
(3 ) the same
What is this question really asking?
Explanation by: Kristina A
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Answer 1
less
INCORRECT
By using the formula Work= Force * change in displacement we can plug in the numbers and get Work= 4.9 joules. This is not less than 1.3 joules. Check your math.
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Answer 2
greater
CORRECT
You didn't get caught by the extra information. All you have to do to answer the question is use the fromula Work= Force * change in displacement and plug the numbers in. By doing this you should get 4.9 joules which is greater than 1.3 joules.
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Answer 3
the same
INCORRECT
By using hte formula Work= Force * change in displacement we can plug in the numbers and get Work= 4.9 joules. This is not equal to 1.3 joules. Check your math. return to top
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What's this question really asking?
You have to ignore the misleading extra infromation. In fact you don't even need the diagram. The only vital information is the fact that it took 1.3 joules of work to pull the cart on the inclined plane and you need to figure out the amount ofwork by using the info that the 9.8 newton cart vertically 0.50 meters. return to top
