| ⇦ | 
| ⇨ |
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: - The de-Broglie wavelength of a proton(charge = 1.6 x 10⁻¹⁹ C, Mass = 1.6 x 10⁻²⁷ kg)
- The mean free path of electrons in a metal is 4 x 10⁻⁸ m. The electric field
- A boat of anchor is rocked by waves whose crests are 100 m apart and velocity
- The e.m.f. of a battery is 2 V and its internal resistance is 0.5 Ω. The maximum
- In a diffraction pattern due to a singleslit of width a, the first minimum is observed
Topics: Magnetic Effects of Current and Magnetism
(167)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- The de-Broglie wavelength of a proton(charge = 1.6 x 10⁻¹⁹ C, Mass = 1.6 x 10⁻²⁷ kg)
- The mean free path of electrons in a metal is 4 x 10⁻⁸ m. The electric field
- A boat of anchor is rocked by waves whose crests are 100 m apart and velocity
- The e.m.f. of a battery is 2 V and its internal resistance is 0.5 Ω. The maximum
- In a diffraction pattern due to a singleslit of width a, the first minimum is observed
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