(b) A boy wishes to walk on ice block at a constant speed. The coefficient of sliding friction for steel on ice is 0.05 and the boy weighs 150 N. Find the force required to keep the boy moving at a constant speed along the ice.
M*g = 150 N = Wt. of the boy = Normal force(Fn).
Fk = u*Fn = 0.05 * 150 = 7.5 N. = Force of kinetic friction.
Fap-Fk = M*a
Fap-7.5 = M*0 = 0
Fap = 7.5 N. = Force applied.
To find the force required to keep the boy moving at a constant speed along the ice, we first need to understand the concept of sliding friction.
Sliding friction opposes the motion between two surfaces in contact. In this case, it is the frictional force between the steel on ice. The force of sliding friction can be calculated using the equation:
F_friction = coefficient of sliding friction * normal force
In this equation, the normal force is the force exerted perpendicular to the surface of contact. In this case, it is the weight of the boy, which is given as 150 N.
So, substituting the values into the formula:
F_friction = 0.05 * 150 N
F_friction = 7.5 N
Therefore, the force required to keep the boy moving at a constant speed along the ice is 7.5 N.