A38 kg crate rests on a floor. a horizontal pulling force of 170 n is needed to start the crate
moving. what is the coefficient of static friction between the crate and the floor?

0.456033049

Explanation:

where N=mg hence

where m is mass of object, g is acceleration due to gravity whose value is taken as , is the coefficient of static friction and F is the applied force.

Making the subject we obtain

and substituting m for 38 Kg, g for and 170 N for  F we obtain

Therefore, the coefficient of static friction is 0.456033049

the force required to move the cart is divided by three or 33.33 n.