A student writes three statements about an atom of beryllium.
The atom has 4 protons, 5 neutrons and 4 electrons.
Statement 1: The electrons and the neutrons are found in the nucleus.
Statement 2: Most of the mass of the atom is due to its electrons.
Statement 3: The atom has an overall charge of +4 because it has 4 protons.
Each statement contains an error.
Write a corrected version of each statement.
Explain why Statement 3 is wrong.
The relative mass of an electron is about 12000\displaystyle \frac{1}{2000}20001.
Show that less than 0.1% of the mass of this atom is due to its electrons.
Explain why the current in a metal wire is a flow of electrons and not a flow of protons.
94 exam-style questions on Edexcel GCSE Physics 10.1 Circuits, charge and current, covering 10.1.1 Structure of the atom, 10.1.2 Circuit diagrams and symbols, 10.1.3 Series and parallel circuits, 10.1.4 Potential difference and voltmeters, 10.1.5 Energy transferred, charge and potential difference, and 10.1.6 Current, ammeters and charge flow. Each one has a worked solution and a mark scheme showing where the marks go.