Water of volume 2 L in a closed container is heatd with a coil of 1 kW. While water is heated, the container loses energy at a rate of 160 J/s. In how much time the temperature of water rise from 27°C to 77°C? (Specific heat of water is 4.2 kJ/kg and that of the container is negligible).

see full answer

Start JEE / NEET / Foundation preparation at rupees 99/day !!

21% of IItians & 23% of AIIMS delhi doctors are from Sri Chaitanya institute !!

An Intiative by Sri Chaitanya

7 min

6 min 2 s

8 min 20 s

14 min

answer is A.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

Mass of water is $ρ = \frac{m}{v}$
$m = ρv = 10^{3} \times 2 \times 10^{- 3} = 2 kg (since 1000 L = 1 m^{3}) Now, using ΔQ = msΔT = (p - p^{'}) \times t \begin{array}{l} = 2 \times 4 .2 \times 10^{3} (77 - 27) = (1000 - 160) t \\ \Rightarrow t = \frac{2 \times 4 .2 \times 10^{3} \times 50}{840} = \frac{500}{60} s = 8 \min 20 s \end{array}$

Watch 3-min video & get full concept clarity

tricks from toppers of Infinity Learn

Result Producing online coaching for JEE/NEET of south India

Largest All India Test Series for JEE/NEET

Best Books for IIT JEE

Best Books for NEET

🔥 Start Your JEE/NEET Prep at Just ₹1999 / month - Limited Offer! Check Now!

Get Expert Academic Guidance – Connect with a Counselor Today!

Result Producing online coaching for JEE/NEET of south India

Largest All India Test Series for JEE/NEET

Best Books for IIT JEE

Best Books for NEET