Question

In an electric heater, $1500$ watt is marked. If this heater is used for $10$ hours continuously, then what will be the consumption of energy

• A. $19\text{unit}$
• B. $40\text{unit}$
• C. $15\text{unit}$
• D. $30\text{unit}$

Answer 1

The correct option is C $15\text{unit}$

Power rating of the heater is given as $P=1500\text{W}$
Time for which the heater has operated $t=10\text{hrs}=36000\text{s}$
Work done $=$ Energy consumed by the heater
$\therefore$ Energy consumed $=$ Power $\times$ Time $=1500\times 36000=5.4\times {10}^7\text{J}=15\text{kWh}=15\text{unit}$ as $1kWh=3.6\times {10}^6\text{J}=1\text{unit}$