⇦ | ![]() | ⇨ |
An electric kettle takes 4A current at 220 V. How much time will it take to boil 1 kg of water from temperature 20⁰C? The temperature of boiling water is 100⁰C
Options
(a) 12.6 min
(b) 4.2 min
(c) 6.3 min
(d) 8.4 min
Correct Answer:
6.3 min
Explanation:
Power = 220 V × 4A = 880 watt = 880 J/s
Heat needed for raising 1 kg of water through 80°C = ms.ΔT × 4.2 J/cal = 100 g × 1 cal/g × 80 × 4.2 J/cal
Therefore, Time taken = (1000 × 1 × 80 × 4.2) / 880 = (336 × 10³) 880 = 382 s = 6.3 min
Related Questions:
- When the speed of electron beam used in Young’s double slit experiment is increased,
- what should be the velocity of an electron so that its momentum becomes equal
- The core of a transformer is laminated because
- Maximum velocity of the photoelectron emitted by a metal is 1.8×10⁶ ms⁻¹.
- An aeroplane flies 400m due to North and then 300m due to south and then flies
Topics: Magnetic Effects of Current and Magnetism
(167)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
18000+ students are using NEETLab to improve their score. What about you?
Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.
Share this page with your friends
Leave a Reply