Question

The heat produced by a $100\, W$ heater in $2\, min$. is equal to

• A. 10.5 kcal
• B. 16.3 kcal
• C. 2.8 kcal
• D. 14.2 kcal.

Answer 1

Answer: (C)

2.8 kcal

Answer 2

Given: Power of heater $(P)=100\, W$ and time $(t)=2 \,\min =120\, sec$. We know that work done to produce heat $(W)=P \times t=100 \times 120=12000 \,J$ $=\frac{12000}{4 \cdot 2 \times 1000}=2 \cdot 8 \,kcal$