Question

What is the kinetic energy of an 80.0 kg football player running at 6.0 m/s?

a)240 J
b)480 J
c)1400 J
d)2900 J

Answer 1

KE = (1/2)·mv²
KE = (1/2) · 80 kg · (6 m/s)²
= 40·36 kg·m/s² = 1440 kg·m/s² = 1440 J
The closest answer is c) 1400 J

Answer 2

We have: Kinetic Energy = Mass × Velocity² / 2
K.E. = mv²/2
Here, m = 80 Kg
v = 6 m/s

Substitute their values into the expression:
K.E. = 80 × 6² / 2
K.E. = 2880 / 2
K.E. = 1440 J (~1400, closest value among the options)

Finally, option C would be your correct answer.

Hope this helps!