Question

a person have a kinetic energy = 32, if the mass increase two times and the velocity decrease four times, What would be the kinetic energy?

Answer 1

ohAnswer:
4
Explanation:
k.e= 1/2 mv²
K.E=1÷4×2
K.E= 1/8
K.E =32/8
K.E=4

Answer 2

Answer:

4 J

Explanation:

Original KE

• KE = 1/2mv²
• ⇒ 32 = 1/2mv²

Mass increases x 2

• KE ∝ m
• m x 2 ∝ KE x 2
• 32 x 2
• KE' = 64

Velocity decreases x 4

• KE' ∝ v²
• KE' x (1/4)² ∝ (1/4)²
• KE' x 1/16 = 64 x 1/16 = 4 J