Question

Time taken by a $836W$ heater to heat one litre of water from ${10}^{0}C$ to ${40}^{0}C$ is:

• A. $50s$
• B. $100s$
• C. $150s$
• D. $200s$

Answer 1

The correct option is C $150s$

We know that,

Heat required by water $=$ heat taken

$t=W/ms\Delta Tt=836/[1\times 4.186\times {10}^{-3}\times (40-10\left)\right]t=150sec$

C is the correct option