friction and inclined planes

Front

What direction does friction act relative to motion?

Back

In the opposite direction.

Front

What is the coefficient of static friction if a box takes 40 N to start moving?

Back

0.54

Front

What is the best expression for the Normal Force on an inclined plane?

Back

F_N = mg cos(ϴ) where ϴ is the angle of inclination.

Front

How do you calculate the force of friction?

Back

Force of friction (F_f) = μ * F_N, where μ is the coefficient of friction and F_N is the normal force.

Front

What is the force of friction between a block of ice that weighs 950 N and the ground if μ = 0.12?

Back

114 N.

Front

What are the units of force due to friction?

Back

Newtons.

Front

What is the relationship between weight and normal force on an inclined plane?

Back

The normal force is less than the weight when on an incline, calculated as F_N = mg cos(ϴ).

Front

What happens to the force of friction if the surface is smoother?

Back

The force of friction decreases.

Front

What is kinetic friction?

Back

Kinetic friction is the frictional force acting between moving surfaces.

Front

What is static friction?

Back

Static friction is the frictional force that prevents two surfaces from sliding past each other.