Assignment:
(a) A particular 240V, 50Hz electrical appliance is rated at 2kW and has a lagging power factor of 0.7.
(i) Determine the appliance’s power factor when it is used on a 60Hz supply.
(ii) Calculate the supply voltage required to maintain the appliance at its rated power when operated off a 60Hz supply.
(b) When placed in series a coil and capacitor resonate at a frequency of 2251Hz and when placed in parallel they resonate at a frequency of 2228Hz. At parallel resonance it is also found that a current of 5mA flows from the supply when the supply voltage is 25V r.m.s.
- Determine the value of the capacitor and the inductance and the resistance of the coil.