±«Óãtv

Scientists often make measurements. The physical quantities they measure fall into two categories: scalars and vectors. Scalar and vector quantities are treated differently in calculations.

Forces are responsible for all the interactions between particles and objects. They can be divided into two categories: contact forces and non-contact forces.

Gravity is one of the most important forces in the universe. An object with mass in a gravitational field experiences a force known as weight.

Forces are responsible for changing the motion of objects. If more than one force is present, the shape of an object can also be changed.

Turning forces are found in many everyday situations and are essential for machines to function. Levers and gears make use of these turning forces to provide an advantage.

Every living thing on Earth is in balance with the pressure of the air or water around it. Pressure helps blood to move around the body and allows organisms to breathe.

The movement of objects can be described using motion graphs and numerical values. These are both used to help in the design of faster and more efficient vehicles.

Falling objects eventually reach terminal velocity - where their resultant force is zero. Stopping distances depend on speed, mass, road surface and reaction time.

Momentum can be thought of as a combination of mass and velocity. Momentum helps explain some of the most important interactions in nature.

Understanding how to approach exam questions helps boost exam performance. Questions will include multiple choice, descriptions and explanations, using mathematical skills and extended writing.