KS2 SATs Science: Forces and Magnets Guide

Types of force

A force is a push or pull. Gravity pulls objects towards the Earth. Friction acts between two surfaces in contact, slowing movement down. Air resistance is a type of friction that acts on objects moving through air.

Balanced and unbalanced forces

When forces on an object are balanced, it stays still or keeps moving at the same speed. When forces are unbalanced, the object speeds up, slows down or changes direction.

Magnets

Magnets have two poles, north and south. Like poles repel each other; opposite poles attract. Magnetic force can act without the objects touching, unlike most other forces.

Levers, pulleys and gears

Simple machines like levers, pulleys and gears allow a smaller force to have a greater effect, making it easier to do work such as lifting a heavy object.

Common mistakes

• Confusing mass (amount of matter) with weight (the pull of gravity on that mass).
• Forgetting that friction can be useful (grip) as well as unwanted (slowing things down).
• Mixing up which magnetic poles attract and which repel.