A rod initially has a charge of +5 nC+5\ \mathrm{nC}+5 nC and a cloth is neutral. Rubbing transfers electrons carrying 8 nC8\ \mathrm{nC}8 nC of negative charge from the cloth to the rod. No charge reaches the surroundings. Which pair gives the final charge on the rod and the total charge of the rod and cloth?
Rod: +13 nC+13\ \mathrm{nC}+13 nC; total: +5 nC+5\ \mathrm{nC}+5 nC
Rod: +13 nC+13\ \mathrm{nC}+13 nC; total: 0 nC0\ \mathrm{nC}0 nC
Rod: −3 nC-3\ \mathrm{nC}−3 nC; total: 0 nC0\ \mathrm{nC}0 nC
Rod: −3 nC-3\ \mathrm{nC}−3 nC; total: +5 nC+5\ \mathrm{nC}+5 nC
91 exam-style questions on Edexcel GCSE Physics 11.1 Charging by friction, covering 11.1.1 Charging insulators by friction, 11.1.2 Forces between charges, 11.1.3 Electrostatic phenomena, and 11.1.4 Earthing and removing charge. Each one has a worked solution and a mark scheme showing where the marks go.