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A pitcher throws a 145 g baseball at a velocity of 30.00 m/s. How much kinetic energy does the ball have?

1 Answer

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Final Answer:

65.25 J is the kinetic energy that the ball has.

Step-by-step explanation:

M = 145g

(Reminder: kg must be used in this formula, thus we need to convert 145g to kg)

M = 145g x 1kg/1000g

(cross out g, then multiply 145 to 1kg)

M = 145kg/1000 = 0.145kg

M = 0.145 kg

V = 30.00 m/s

Solution:

KE = 1/2mv^2

KE = 1/2(0.145kg)(30.00m/s)^2

(Square first the velocity)

KE = 1/2(0.145kg)(900.00m^2/s^2)

KE = 1/2(130.5 kg*m^2/s^2)

KE = 65.25 kg*m^2/s^2

(Reminder: 1 kg*m^2/s^2 = 1 J)

KE = 65.25 J

Final Answer:

65.25 J is the kinetic energy that the ball has.

User Jason Leach
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