A heater of 220 V heats a volume of water in 5 minutes time. A heater of 110 V heats the same volume of water. Find time of heating.

Question

A heater of 220 V heats a volume of water in 5 minutes time. A heater of 110 V heats the same volume of water. Find time of heating. (A) 1000 s (B) 1200 s (C) 1100 s (D) 1250 s

Tardigrade Admin · Accepted Answer

Heat produced in the first case = (2202/R) × 5 × 60 ...(i) Heat produced in the second case = (1102/R) × t or t = (220 × 220 × 5 × 60/110 × 110) = 20 × 60s = 1200 s

Q. A heater of $220 V$ heats a volume of water in $5$ minutes time. A heater of $110 V$ heats the same volume of water. Find time of heating.

1000 s

1200 s

1100 s

1250 s

Heat produced in the first case = $\frac{22 0 ^{2}}{R} \times 5 \times 60$ ... $(i)$
Heat produced in the second case = $\frac{11 0 ^{2}}{R} \times t or t = \frac{220 \times 220 \times 5 \times 60}{110 \times 110}$
= $20 \times 60 s$ = 1200 s

Q. A heater of 220V heats a volume of water in 5 minutes time. A heater of 110V heats the same volume of water. Find time of heating.