Test – Friction

John is pushing a heavy box across a wooden floor. The box was initially stationary, but after applying enough force, it starts to move. Explain why the force needed to start moving the box is greater than the force needed to keep it moving at constant speed.

A cyclist is riding their bicycle on a flat road. They stop pedaling and eventually come to a stop. Name two types of friction acting on the bicycle and explain how each one contributes to slowing it down.

Sarah notices that her car’s brakes don’t work as well on a rainy day compared to a dry day. Using your knowledge of friction, explain why this happens.

In a factory, heavy crates are moved by placing them on rollers rather than dragging them across the floor. Explain why this method requires less force, using your understanding of different types of friction.

A student claims that increasing the surface area of an object will increase the friction acting on it. Is this statement correct for solid friction? Explain your answer with reference to the factors that affect friction.