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प्रश्न
Three heaters each rated 250 W, 100 V are connected in parallel to a 100 V supply. Calculate:
- the total current taken from the supply
- the resistance of each heater and
- the energy supplied in kWh to the three heaters in 5 hours.
उत्तर
Given,
Power, p = 250 w
Voltage, v = 100 v
- Current through each heater, I = ?
As p = VI
I = `"P"/"V"`
= `250/100`
= 2.5 A
∴ Current taken for the three heaters = 3 × 2.5
= 7.5 A - resistance for each heater, R = `"V"/"I"`
= `100/2.5`
= 40 Ω - Time for which energy is supplied, t = 5h
As, Energy, E = p × t
For each heater E = 250 × 5
= 1250 wh or E = 1.25 kwh
Energy for three heaters = 3 × 1.25
= 3.75 kwh
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