Question 1
The electromotive force (e.m.f.) of a battery is 7.5 V .
Define the term electromotive force.
The electromotive force (e.m.f.) of a battery is 7.5 V .
Define the term electromotive force.
(electrical) work done moving a unit charge around a (complete) circuit
work done AND moving a charge (in a circuit)
The unit of the two electrical quantities electromotive force (e.m.f.) and potential difference (p.d.) is the volt (V).
State one other similarity between e.m.f. and p.d.
both relate to energy per unit charge
State one difference between e.m.f. and p.d.
e.m.f. applies to the whole circuit / source or p.d. to one (or more) component or energy conversion to electrical for e.m.f. or from electrical for p.d.
Define potential difference (p.d.).
work done in passing charge through / across a component
work done per unit charge
State the equation which defines electromotive force (e.m.f.) E.
(definition of emf:) E=W / Q
The e.m.f. of a battery is 9.0 V . The battery is in a circuit.
Calculate the work done by the battery when it moves a charge of 30 C around a complete circuit.
270 J
W = EQ OR 9.0 × 30