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Read the following passage and answer the questions that follow :
Swati, a class 10 student, observes that when she passes close to the refrigerator in her kitchen, she feels the heat, although the things kept inside the refrigerator are cool.
(a) Describe the cause of heating in the above-mentioned case.
Swati, a class 10 student, observes that when she passes close to the refrigerator in her kitchen, she feels the heat, although the things kept inside the refrigerator are cool.
(a) Describe the cause of heating in the above-mentioned case.
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(a) A part of current is consumed into useful work and rest is expended in heat to raise the temperature of gadget. (1 Mark) (any other suitable explanation)
(b) $W=V \times Q= VIt = IR \times It$
$H = I^2Rt$ / $\frac{V^2}{R}t$ (1 Mark)
(c) (i) Electric heater, Oven, Electric iron (Any two, Any other) (1+1 Marks)
OR
(c) (ii) When 1 kilowatt of power is used for 1 hour then energy consumed is 1 kWh (1 Mark)
1 kWh = $3.6 \times 10^6\text{J}$ (1 Mark)
(b) $W=V \times Q= VIt = IR \times It$
$H = I^2Rt$ / $\frac{V^2}{R}t$ (1 Mark)
(c) (i) Electric heater, Oven, Electric iron (Any two, Any other) (1+1 Marks)
OR
(c) (ii) When 1 kilowatt of power is used for 1 hour then energy consumed is 1 kWh (1 Mark)
1 kWh = $3.6 \times 10^6\text{J}$ (1 Mark)