Newton's Block !!!!!
What is the acceleration of a man of
plus the block of
system shown in the figure if the man applies a force of
on the string (the plane is fixed , smooth , horizontal). Also the string is horizontal.
Give your answer in .
The answer is 1.2.
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1 solution
I solved this on the third attemp. Total mass of system is 40+10 = 50kg. So simply 30N/50kg = 0.6 m/s^2. Relative to the wider world. That wasn't it!
So is it a trick question? The plane is smooth and the man simply can't get the friction to apply 30N to the string. So try 0! No. That wasn't it.
Well the block is acc'ing at 0.6 m/s^2 left and the man 0.6 to the right so the block is accelerating RELATIVE to the man at 1.2 m/s^2 That's the "Right" answer.