A large metal crate is carried on the flatbed of a truck moving forward along a straight horizontal road at a constant speed. Only two horizontal forces act on the crate: air resistance and the friction between the crate and the flatbed of the truck.
Which of the following correctly describes the directions and the magnitudes of these two forces?
They act in the same direction and have different magnitudes.
They act in the same direction and have the same magnitude.
They act in opposite directions and have different magnitudes.
They act in opposite directions and have the same magnitude.
245 exam-style questions on CIE IGCSE Physics 1.5 Forces, covering 1.5.1a Forces, resultant force and motion, 1.5.1b Load–extension graphs and the spring constant, 1.5.1c Friction and drag, 1.5.1d Force, mass and acceleration, 1.5.1e Motion in a circular path, 1.5.2a Moment of a force, 1.5.2b Principle of moments and equilibrium, and 1.5.3 Centre of gravity and stability. Each one has a worked solution and a mark scheme showing where the marks go.