Question

- A fridge has a maximum static friction force

Answer 1

Answer:

They will move the fridge if they all push in the same direction, but it will not move with constant velocity

Explanation:

The maximum static friction force is

$F_f = -250 N$ (negative sign since its direction is opposite to the push applied by the people)

Sam can apply a force of 130 N, while Amir and Andre can apply a push of 65 N each, so the total force that they can apply, if they push in the same direction, will be:

$F=130 + 65 +65=260 N$

This force is larger than the frictional force, so the fridge will start moving.

However, the net force on the fridge will be:

$\sum F = 260 N - 250 N = 10 N$

And according to Newton's second law,

$\sum F = ma$

where m is the mass of the fridge and a its acceleration, since the net force is not zero, then the fridge will have a non-zero acceleration, so it will not move with constant  velocity.