The resistance of a lamp is found using the value of the potential difference (p.d.) across it and the value of the current flowing through it. Which statement gives the correct way to combine the uncertainties in the p.d. and in the current?
- AAdd together the actual uncertainty in the p.d. and the actual uncertainty in the current.
- BAdd together the percentage uncertainty in the p.d. and the percentage uncertainty in the current.
- CSubtract the actual uncertainty in the current from the actual uncertainty in the p.d.
- DSubtract the percentage uncertainty in the current from the percentage uncertainty in the p.d.