The minimum force that must be applied to a machine with a mechanical advantage of 5 in order to lift a 100-kg crate is
A) 20 N.
B) 196 N.
C) 500 N.
D) 4900 N.

Question

Quizplus · Accepted Answer

To lift a 100-kg crate with a mechanical advantage of 5, the minimum force required can be found using the formula: 
Minimum Force = Weight of Crate / Mechanical Advantage 
Minimum Force = 100 kg / 5 
Minimum Force = 20 kg 
To convert from kg to N, we multiply by the acceleration due to gravity, which is 9.8 m/s^2: 
Minimum Force = 20 kg x 9.8 m/s^2 
Minimum Force = 196 N 
Therefore, the minimum force required to lift the crate is 196 N, which corresponds to choice (B).

The Minimum Force That Must Be Applied to a Machine