When an object is falling, the two main forces acting on it are weight close weightA force that acts on mass, pulling it down, due to gravity. Weight is a force and forces are measured in newtons (N).

Velocity-time graphs show how the velocity (or speed) of a moving object changes with time. These graphs also show if the object is moving at a constant speed or accelerating, decelerating, or still.

Tomography—cross-sectional imaging based on measuring radiation transmitted through an object along different directions—enables non-invasive imaging of hidden stationary objects, such as internal ...