A stone of mass 10 kg is dropped from a height of 5 m. Calculate its initial potential energy and its velocity before reaching the ground.
Answers
Explanation:
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Explanation:
(a). Mass of the Body = 10 kg. Height = 10 m. Acceleration due to gravity = 9.8 m/s². Using the Formula,Potential Energy = mgh = 10 × 9.8 × 10 = 980 J. (b). Now, By the law of the conservation of the Energy, Total amount of the energy of the system remains constant. ∴ Kinetic Energy before the body reaches the ground is equal to the Potential Energy at the height of 10 m. ∴ Kinetic Energy = 980 J. (c). Kinetic Energy = 980 J. Mass of the ball = 10 kg. ∵ K.E. = 1/2 × mv² ∴ 980 = 1/2 × 10 × v² ∴ v² = 980/5 ⇒ v² = 196 ∴ v = 14 m/s.