A really useful revision tactic (and also quite a common type of exam question) involves looking at the differences that exist between two related things in the same area of physics. These comparisons can be very simple, such as the definitions of scalars and vectors, or they can be more complicated, such as competing theories … Continue reading Compare and Contrast
Nuclear Reactor Components
In a highly simplified view of nuclear fission reactors, we can reduce the key elements to just two components that control the chain reaction. Control rods are used to reduce the number of free neutrons and the moderator is used to slow down the neutrons so that they can be captured by other nuclei to … Continue reading Nuclear Reactor Components
Balancing Nuclear Equations
An easy way to pick up marks in the GCSE Physics exam is by balancing nuclear equations. To do this, you need to apply the law of the conservation of mass, which says the total mass before a nuclear change takes place is equal to the total mass after the change has occurred. This is … Continue reading Balancing Nuclear Equations
Nuclear Fission Processes
Nuclear fission is the process whereby a nucleus is split into two smaller nuclei. Fission happens when a nucleus absorbs an extra neutron and becomes highly unstable, instantly splitting apart. The starting nucleus is known as the 'parent' and the split fragments are known as 'daughter' nuclei. The parent nucleus does not split exactly in … Continue reading Nuclear Fission Processes
Moderators and Control Rods
If nuclear fission processes are used to generate electricity in a nuclear power station, it is absolutely vital to manage the neutrons that are released during nuclear fission so that their number remains constant and energy is released at a constant rate. This management is achieved using control rods and a moderator, which serve two … Continue reading Moderators and Control Rods
Chain reactions
Nuclear fission (see here) is caused when an atom absorbs an extra neutron, causing the nucleus to split apart. The resultant nuclear reaction releases more neutrons, which can go on to cause further fission events. This sequence, where released neutrons go on to cause further fissions, is known as a chain reaction. If the number … Continue reading Chain reactions
