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Attempt either (a) or (b) :
(a) A person was repairing an electric heater. He observed that there were three different connecting wires of three different colours in the cable attached to the heater.
(i) What are these three different wires called ? Name them colourwise.
(ii) What is the value of standard potential difference at which electricity is supplied in Indian homes for lighting?
(iii) What is the role of (I) earthing and (II) fuse in domestic electric circuits ?
(a) A person was repairing an electric heater. He observed that there were three different connecting wires of three different colours in the cable attached to the heater.
(i) What are these three different wires called ? Name them colourwise.
(ii) What is the value of standard potential difference at which electricity is supplied in Indian homes for lighting?
(iii) What is the role of (I) earthing and (II) fuse in domestic electric circuits ?
Show SolutionHide Solution↓
(a) (i) Live wire - Red
(
frac{1}{2})
Neutral wire - Black
(
frac{1}{2})
Earth wire - Green
(
frac{1}{2})
(ii) 220V
(1)
(iii) (I) Earth wire provides a low resistance conducting path for current and thus, protect us from electric shock due to leakage of electric current to metallic body of electrical appliances.
(1)
(II) Fuse is a safety device which melts and breaks the electric circuit when unduly high electric current flows due to overloading and prevents damage to appliances and circuit.
(1)
(
frac{1}{2})
Neutral wire - Black
(
frac{1}{2})
Earth wire - Green
(
frac{1}{2})
(ii) 220V
(1)
(iii) (I) Earth wire provides a low resistance conducting path for current and thus, protect us from electric shock due to leakage of electric current to metallic body of electrical appliances.
(1)
(II) Fuse is a safety device which melts and breaks the electric circuit when unduly high electric current flows due to overloading and prevents damage to appliances and circuit.
(1)