Advertisements
Advertisements
प्रश्न
Give two precautious that you would take while putting off an electric switch.
Advertisements
उत्तर
We will make sure that no naked wire is touching the button of the switch and neither the hand nor the switch is wet.
APPEARS IN
संबंधित प्रश्न
State the S.I. units of electrical power and electrical energy.
(i) Define the household unit of electricity.
(ii) What is the voltage of the electricity that is generally supplied to a house?
A coil of copper wire is connected to a galvanometer. What would happen if a bar magnet is:
(i) Pushed into the coil with its north pole entering first?
(ii) Held at rest inside the coil?
(iii) Pulled out again?
Name two common material used for heating elements.
Why is heating element wound on a long porcelain rod in a room heater.
Why is the heating element of an electric oven wound on a helix? State the reason.
A device is used to transform 12 V a.c. to 200 V a.c. What is the name of this device? Name the principle on which it works.
The equation I2R seems to suggest that the rate of heating in a resistor is reduced if resistance decreases, whereas equation P = V2/R suggests just the opposite. How do you reconcile this problem?
A battery of e.m.f. 12V and internal resistance 1.6 Ω is connected to two resistors of 4Ω and 6Ω connected in parallel. Calculate:
(i) the current drawn from the battery,
(ii) the power dissipated in each resistor,
(ii)the total power supplied by the battery.
The resistance of filament of an electric heater is 500 Ω It is operated at 200V for 1 hour daily. Calculate the current drawn by the heater and the energy consumed in joule.
