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3 years ago

14

A 0.14-kg baseball is moving at 41 m/s. A 0.058-kg tennis ball is moving at 67 m/s. Which of the two balls has higher kinetic en

ergy?

1 answer:

lbvjy [14]3 years ago

6 0

Answer:

The kinetic energy of tennis ball is higher than that of baseball.

Explanation:

mass of baseball $m_{b}$ = 0.14 kg

velocity of baseball $v_{b}$ = 41 m/s

mass of tennis ball $m_{t}$ = 0.058 kg

velocity of tennis ball $v_{t}$ = 67 m/s

To find: the kinetic energy of baseball $KE_{b}$ and tennis ball $KE_{t}$

We know that the kinetic energy is given by the equation,

KE = $\frac{mv^{2}}{2}$

the kinetic energy of baseball $KE_{b}$ = $\frac{m_{b}v_{b} ^{2}}{2}$

= $\frac{0.14 * 41^{2}}{2}$

= 117.67 J

the kinetic energy of tennis ball $KE_{t}$ = $\frac{m_{t}v_{t} ^{2}}{2}$

= $\frac{0.058 * 67^{2}}{2}$

= 130.181 J

Hence $KE_{t}$ > $KE_{b}$ , the kinetic energy of tennis ball is higher than that of baseball

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