The coefficient of friction sliding on wood is 0.30. The force needed to slide a wooden block weighing 500N across a horizontal surface is:

a. 50N
b. 150N
c. 300N
d. 500N

M*g = 500 N. = Normal force(Fn).

Fk = u*Fn = 0.3 * 500 = 150 N. = Force of kinetic friction.

Fap-Fk = M*a
Fap-150 = M*0 = 0
Fap = 150 N. = Force applied.

Ali

To find the force needed to slide a wooden block across a horizontal surface, we can use the formula:

Force of friction = coefficient of friction * normal force

Here, the normal force is the weight of the wooden block, which is given as 500N.

So, substituting the values into the formula:

Force of friction = 0.30 * 500N

Force of friction = 150N

Therefore, the force needed to slide the wooden block is 150N.

So, the correct answer is:

b. 150N