The set up in the figure is used to study the relationship between current (I) and potential difference (V) for a wire X.
If the material X is a copper wire, the relationship between V and I when the switch is closed at constant temperature is:
Hooke’s law.
Ohm’s law.
Coulomb’s law.
Lenz’s law.
The ammeter is connected as shown because it has:
A very high resistance and so allows little current to flow through it.
Very low resistance and so does not alter the current flowing through it.
Very high resistance and so allows high current to flow through it.
Very low resistance and so alters the current flowing through it.
The rheostat Y is used to:
Vary electromotive force.
Vary the resistance of the wire.
Vary the current in the circuit.
Keep the temperature constant.
An impulse of 100 N is applied to an object.
If this same impulse is delivered over a longer time interval:
The momentum transferred will be increased.
The force involved will be increased.
The momentum transferred will be decreased.
The force involved will be decreased.
The value of X for which the galvanometer in the figure shows a null deflection is:
1Ω.
4.5 Ω.
8Ω.
4Ω.
