The Physics Question Bank

A system is the object, or group of objects, that we decide to focus on in a physics problem. It is like drawing an invisible box around the thing we are studying. Anything inside the box is part of the system. Anything outside the box is the surroundings. For AQA GCSE Physics, systems are usually…

In a parallel circuit, the current has more than one route to take. Each extra branch gives the charge another pathway through the circuit. This means more charge can flow each second from the cell or power supply. If more current flows for the same potential difference, the overall resistance must be lower. So, when…

GCSE Physics becomes hard when pupils have to do more than remember a definition. The tricky parts usually involve equations, graphs, invisible ideas, or explaining cause and effect clearly. 1. Current, potential difference and resistance This is one of the biggest problem areas in GCSE Physics. Pupils often think current is “used up” as it…

Isotopes are different versions of the same element. Atoms of the same element always have the same number of protons. This is what makes them that element. For example, every carbon atom has 6 protons. If it did not have 6 protons, it would not be carbon. Isotopes have the same number of protons, but…

Contamination and irradiation are often mixed up, but they mean different things. Contamination is when unwanted radioactive material gets onto or inside something. For example, radioactive dust could get onto a person’s skin, clothing, food or equipment. The danger is that the radioactive material stays there and keeps giving out radiation. This means the person…

Our ideas about the atom have changed over time. Each model was accepted until new evidence showed that it needed to be improved. At first, Dalton described atoms as tiny solid spheres. He thought atoms were very small particles that could not be divided. This was a useful early model, but it did not explain…

A transformer changes the size of an alternating voltage. It only works with alternating current because the magnetic field needs to keep changing. A transformer has two coils of wire wrapped around an iron core. The input coil is called the primary coil and the output coil is called the secondary coil. When an alternating…

A split-ring commutator is one of the clever parts of a simple DC motor. Its job is to make sure the coil keeps turning the same way. In a motor, the coil sits inside a magnetic field. When a current passes through the coil, the two sides of the coil feel forces in opposite directions.…