A body projected vertically from the earth reaches a height equal to earth’s radius

⇦

⇨

A body projected vertically from the earth reaches a height equal to earth’s radius before returning to the earth. The power exerted by the gravitational force is greatest

Options

(a) at the highest position of the body
(b) at the instant just before the body hits the earth
(c) it remains constant all through
(d) at the instant just after the body is projected

Correct Answer:

at the instant just before the body hits the earth

Explanation:

Power exerted by a force is given by P = F.v. When the body is just above the earth’s surface, its velocity is greatest. At this instant, gravitational force is also maximum. Hence, the power exerted by the gravitational force is greatest at the instant just before the body hits the earth.

Related Questions:

1. A lift is moving down with acceleration a.A man in the lift drops a ball
2. Three capacitors of capacitances 3 μF, 10 μF and 15 μF are connected in series
3. A parallel plate capacitor with air between the plates has a capacitance of 9 pF.
4. If 20% of a radiactive element decays in 10 days, then amount of original material left
5. In n-type semiconductor, electrons are majority charge carriers

Topics: Work Energy and Power (94)
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