High School

### Speed of Baseball Pitches

Major League Baseball pitchers throw a pitch called a changeup, which looks like a fastball leaving the pitcher's hand but has less speed than a typical fastball. How much more kinetic energy does a 148 km/h (92 mph) fastball have than a 125 km/h (78 mph) changeup?

Express your answer as a percentage of the kinetic energy of the changeup.

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1.56. Write conversion factor(s) for each of the following unit conversions:
(a) picoseconds to seconds
(b) meters to centimeters
(c) nanoseconds to milliseconds
(d) square meters to square kilometers

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1.57. A single strand of natural silk may be as long as [tex]$4.0 \times 10^2$[/tex] meters.
(a) How many significant figures are in that value?
(b) Express that length in kilometers, centimeters, inches, and feet.

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1.58. Olympic Mile

An Olympic "mile" is actually 1500.0 meters.
(a) How many significant figures are in that value?
(b) Express that distance in kilometers, centimeters, inches, and feet.

Answer :

The kinetic energy of a 148 km/h fastball is approximately 33.792% higher than that of a 125 km/h changeup.

The kinetic energy of an object is given by the formula [tex]KE = 1/2 * m * v^2[/tex], where m is the mass of the object and v is its velocity.

To compare the kinetic energy of a fastball and a changeup, we need to determine the difference in their velocities.

The difference in velocities can be calculated by subtracting the velocity of the changeup from the velocity of the fastball.

With the given velocities, the difference in velocities is 148 km/h - 125 km/h = 23 km/h.

To find the percentage difference in kinetic energy, we can use the formula [tex](v1^2 - v2^2) / v2^2 * 100[/tex], where v1 is the velocity of the fastball and v2 is the velocity of the changeup.

Plugging in the values, we get [tex]((148^2 - 125^2) / 125^2) * 100 = 33.792%[/tex]

To Know More about kinetic visit:

brainly.com/question/31627294

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