Question

When the momentum of a body increased by 10% , then it's k.E. Increases by:?

Answer 1

Answer:

21%

Explanation:

using the relation

E = P^2 / 2m

if P is increased by 10% then P' = 1.1 P

and therefore E' = 1.21 E

( since 1.1^2 = 1.21)

and therefore the kinetic energy increases by 21%

Answer 2

Answer:

K = p² / (2m)

From above

K2/K1 = (p2/p1)²

Subtract 1 from both the sides

K2/K1 - 1 = (p2/p1)² - 1

(K2 - K1)/K1 = (p2/p1)² - 1

ΔK/K1 = (p2/p1)² - 1

ΔK = K1 × [(p2/p1)² - 1]

ΔK = 100% × [(110%/100%)² - 1] = 21%