(a(i))[1]
State how the resistance of the wire varies with $l$.
(a(ii))[1]
State how the resistance of the wire varies with $A$.
(b)[2]
Calculate the resistance between the two opposite faces A and B of the cube.
(c(i))[2]
Explain what is meant by electromotive force (e.m.f.).
(c(ii))[3]
Calculate the potential difference across the $1.0\,\text{m}$ section of wire.
(c(iii))[3]
Describe and explain what happens to the trace on the oscilloscope screen as the sliding contact is moved along the wire.
(d(i))[1]
State one advantage of using two cells in parallel rather than a single cell.
(d(ii))[2]
State and explain the effect on the trace in (c)(iii) of adding the second cell in parallel.