Fig. 9.1 illustrates an electric circuit containing the uninsulated resistance wire XY. A teacher demonstrates to some students how the circuit is completed by putting the contact C at different positions along wire XY. The circuit has a 6.0 V d.c. supply, an ammeter marked A, a fixed resistor of 8.0 Ω, the uninsulated resistance wire XY with point P between X and Y, and a movable contact C.
(a)[2]
State and explain the effect on the ammeter reading when contact C is shifted from Y to X.
(b)[3]
Calculate the ammeter reading when contact C is positioned at X.
(c)[2]
Calculate the total resistance of the resistance wire between X and P together with the fixed resistor.
(d)[2]
An electric current in the circuit causes two effects. Put a tick (✓) beside the two effects from the list below. The effects listed are: gravitational, magnetic, heating, sound, X-ray emissions.
Worked solution & mark scheme
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Ammeter reading increases” …