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If the initial velocity of the baseball hit is 28 m/s, what was the angular velocity about the shoulder joint (in degrees) at the point of ball contact?

User Anuj Kalia
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1 Answer

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Final answer:

To find the angular velocity in degrees given a linear velocity and the distance from the point of rotation, we use the formula ω = v/r. For example, with a pitcher's arm where the linear velocity is 35.0 m/s and the ball is 0.300 m from the elbow joint, the angular velocity in radians per second is calculated as 116.67 rad/s, which converts to approximately 6682.81 degrees/s.

Step-by-step explanation:

If the initial velocity of a baseball hit is 28 m/s, we need additional information such as the distance from the point of rotation (shoulder joint) to the baseball to compute the angular velocity. However, using the provided reference scenario where a baseball pitcher rotates the forearm about the elbow and the velocity of the ball in the pitcher's hand is 35.0 m/s at a distance of 0.300 m from the elbow joint, we can calculate the angular velocity of the forearm with the formula:

v = rω

Where:

  • v is the linear velocity of the ball (35.0 m/s)
  • r is the radius from the elbow joint to the ball (0.300 m)
  • ω is the angular velocity we want to find

By rearranging the formula to solve for ω, we get:

ω = v/r

Substituting the known values:

ω = 35.0 m/s / 0.300 m

ω = 116.67 rad/s

To convert rad/s to degrees/s, we use the conversion factor of 180/π:

ω in degrees/s = 116.67 rad/s × (180/π)

ω in degrees/s = 6682.81 degrees/s

Hence, the angular velocity of the pitcher's forearm in degrees per second is approximately 6682.81 degrees/s.

User Peter Corless
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