How Do You Calculate the Mass of a Trailer Using Newton's Second Law?

AI Thread Summary
To calculate the mass of a trailer using Newton's Second Law, the scenario involves a car pulling a trailer at a steady speed of 10 m/s with a pull of 100N, indicating balanced forces due to constant resistance. When the car accelerates at 0.5 m/s², the pull increases to 150N, suggesting a net force of 50N after accounting for the constant resistance. By applying the formula F=ma, the mass of the trailer is determined by dividing the net force (50N) by the acceleration (0.5 m/s²), resulting in a calculated mass of 100kg. The calculation is confirmed as correct by another participant in the discussion. This method effectively applies Newton's Second Law to find the mass of the trailer.
SeanGillespie
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Homework Statement


A car pulls a trailer along a level road at a steady speed of 10 m/s and the pull on the trailer is 100N. When the car accelerates at 0.5 m/s2 the pull on the trailer is 150N.
Assuming the resistance to motion to be constant, find the mass of the trailer.

Homework Equations


F=ma

The Attempt at a Solution



My assumption is that since there is no acceleration in the first case, the pull on the trailer (100N) must be balanced by a resistive force (100N). Since the resistance to motion is said to be constant, in the latter case the resistance would still be 100N.

The net force while accelerating would be 50N (150N - 100N), so using F = ma, mass should be found by dividing 50N by 0.5 m/s2.

I've calculated the trailer's mass as 100kg.

I feel uneasy about the question, it seemed fairly straight-forward, just wanting an outside opinion... have I calculated this correctly?
 
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Your calculation looks fine to me!
 

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