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A 58-kg boy swings a baseball bat, which causes a 0.140-kg baseball to move toward 3rd base with a velocity of 38.0 m/s.

Calculate the kinetic energy of the baseball (rounding your answer to the integer).

User Jenissa
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2 Answers

1 vote

Answer:

101 J

Step-by-step explanation:

User Tdhsmith
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2 votes

Answer:


\boxed {\boxed {\sf 101 \ Joules}}

Step-by-step explanation:

Kinetic energy can be found using the following formula:


KE=(1)/(2)mv^2

The mass of the baseball is 0.140 kilograms and the velocity is 38.0 meters per second.


m= 0.140 \ kg \\v= 38.0 \ m/s

Substitute the values into the formula.


KE=(1)/(2) [0.140 \ kg][(38.0 \ m/s)^2]

First, evaluate the exponent.

  • (38.0 m/s)²= 38.0 m/s * 38.0 m/s = 1444 m²/s²


KE=(1)/(2)(0.140 \ kg)(1444 \ m^2/s^2)

Multiply the two numbers in parentheses together.


KE=(1)/(2)(202.16 \ kg*m^2/s^2)

Multiply the fraction by the number, or divide the number by 2.


KE=101.08 \ kg*m^2/s^2

Round to the nearest whole number. The 0 in the tenth place tells us we can leave the number as is.


KE\approx 101 \ kg*m^2/s^2

1 kg*m²/s² is equal to 1 Joule. Therefore, our answer of 101 kg*m²/s² is equal to 101 Joules (J).


KE\approx 101 \ J

The kinetic energy of the baseball is about 101 Joules.

User KOVIKO
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