Calculating Work Done by a Child Pulling a Toy Car

AI Thread Summary
To calculate the work done by a child pulling a toy car, the formula used is work = force x displacement. In this case, the work is calculated as W = (123 N)(10 m) cos(25 degrees), resulting in 1114.8 J. The child's height and the car's mass do not affect the calculation of work in this scenario. The consensus is that the calculation is correct, and the child's height is irrelevant to the problem. Overall, the work done by the child is confirmed to be 1114.8 J.
j doe
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Homework Statement


A child 1.52 meters tall pulled a 2.54 kg toy car for 10 meters. The car has a string attached to it, and when pulled creates a 25 degree angle from the horizon. If the string has a force of 123 N on it while being pulled, how much work did the child do?

Homework Equations


work = force x displacement

The Attempt at a Solution


W = (123 N)(10 m) cos(25 degrees) = 1114.8 J

is this correct? does the child's height have anything to do with the problem?
 
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j doe said:
W = (123 N)(10 m) cos(25 degrees) = 1114.8 J

is this correct?
Yep! Good!

j doe said:
does the child's height have anything to do with the problem?
Nope. (Neither does the car's mass.)
 
Seems okay to me and no, the child's height is irrelevant.
 
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