A heating element is connected across one cell, then across two cells. The potential difference (p.d.) across the heating element and the current in it are measured in each case.
For 1 cell, the p.d. is 3.2 V and the current is 0.20 A.
For 2 cells, the p.d. is 6.3 V and the current is 0.35 A.
What is the change in the resistance of the heating element when the number of cells is increased from one to two?
It decreases by 2.0 Ω2.0\ \Omega2.0 Ω.
It increases by 2.0 Ω2.0\ \Omega2.0 Ω.
It increases by 3.1 Ω3.1\ \Omega3.1 Ω.
It increases by 18.0 Ω18.0\ \Omega18.0 Ω.
132 exam-style questions on CIE IGCSE Physics 4.2.4a Resistance. Each one has a worked solution and a mark scheme showing where the marks go.