A body of mass 16 kg accelerates vertically down with a force of 8 N. What is the minimum force required to make it move upward with the same acceleration? [Take #"g = 10 m/s"^2#].
1 Answer
It would require an upward force of 328 N (-328 N).
Explanation:
I am not sure I am correctly visualizing the situation. I will assume that the body will remain fixed in place by static friction if the applied downward force is less than 8 N.
In the first case the applied force,
So 168 N is able to break the static friction and start the mass moving. Now in case 2, we want it to accelerate it upward. Since we have already done an equation in which downward forces are positive, we will continue to use that convention. To have the same value of acceleration the total force,
The question is what does the applied force,
We said above that
Then
I hope this helps,
Steve