A little question~ (1 Viewer)

[shinji]

http://i18.photobucket.com/albums/b149/drifter_/question.jpg
^ for that question, can anyone please explain to me why it is C, and not B.

Coz from what i gather, there is no acceleration as the force that is acting upon the astronaut is constant. Therefore it must be "coasting"... the greatest acceleration would be (B) .. wouldn't it?

thanks in advanced

 

[helper]

Its Force time graph not velocity time.

 

[rama_v]

Force is maximum between times U and V and since m is constant, then by F=ma, a is also maximum

 

[shinji]

ooooo k.. wat bout T - U ? lol.

 

[rama_v]

ooooo k.. wat bout T - U ? lol.

between T and U the gradient is steepest. But that does not mean that force is maximum - force is maximum when the graph is at a maximum, and thats from the period U-V. Oh also, there is a common misconception that a force acts upon a body when it is moving at a constant velocity. THis is not true. A force only acts upon a body when there is an acceleration. No acceleration = no force. If force is constant then acceleration is constant. Therefore max force = max acceleration.