Q1 Which law define the heat produced by an electrical appliance?
- (a) Coulomb’s Law
- (b) Kirchhoff’s law
- (c) Gauss Law
- (d) Joule’s law of heating
- (d) Joule’s law of heating
Q2 kWh is the unit of:
- (a) Charge
- (b) Power
- (c) Electrical Energy
- (d) None
- (c) Electrical Energy
Q3 How much heat will be produced by a heater of 1200W in 1 minute?
- (a) 72000J
- (b) 52000J
- (c) 1200J
- (d) 12000J
- (a) 72000J
Use the formula H= `I^{2}`Rt
Q4 How much current will be drawn by a motor of 5hp. from 220Vsupply?
- (a) 18.8A
- (b) 16.95A
- (c) 5A
- (d) 20.7A
- (b) 16.95A
Use the formula of Power P =V/I
1 hp = 746Watt
Q5 Three bulbs 40W, 60W and 100W are connected in parallel and given 220V supply. Which bulb will draw more current?
- (a) 40W bulb
- (b) 60W bulb
- (c) 100W bulb
- (d) None
- b) 100W bulb
Q6 Insulators also show Joule’s heating effect.(T/F)
- a) True
- b) False
- b) False
Q7 Joule is the commercial unit of electrical power. (T/F)
- a) True
- b) False
- b) False
The commercial unit of power is Horse Power
Q8 The commercial unit of electric energy is ------------.
- (a) Watt
- (b) Joule
- (c) KWh
- (d) None of these
- (c) kWh
Q9. which of the following is true about heating elements in heaters
- a) have low resistivity and low melting point
- b) have high resistivity and high melting point
- c) have low resistivity and high melting point
- d) have high resistivity and low melting point
- b) have high resistivity and high melting point
Q10 Two electric bulbs of 40 W each connected in series.The power consumed by the combination will be
- (a) 20W
- (b) 60W
- (c) 80W
- (d) 100W
- (a) 20W
