Easy MCQ +4 / -1 PYQ · JEE Mains 2021

An electric appliance supplies 6000 J/min heat to the system. If the system delivers a power of 90W. How long it would take to increase the internal energy by 2.5 $\times$ 103 J ?

  1. A 2.5 $\times$ 10<sup>2</sup> s Correct answer
  2. B 4.1 $\times$ 10<sup>1</sup> s
  3. C 2.4 $\times$ 10<sup>3</sup> s
  4. D 2.5 $\times$ 10<sup>1</sup> s

Solution

$\Delta$Q = $\Delta$U + $\Delta$W<br><br>$${{\Delta Q} \over {\Delta t}} = {{\Delta U} \over {\Delta t}} + {{\Delta W} \over {\Delta t}}$$<br><br>$${{6000} \over {60}}{J \over {\sec }} = {{2.5 \times {{10}^3}} \over {\Delta t}} + 90$$<br><br>$\Delta$t = 250 sec

About this question

Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law

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