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AP®︎/College Physics 1

Course: AP®︎/College Physics 1 > Unit 7

Lesson 6: Angular momentum and angular impulse
Science
AP®︎/College Physics 1
Torque and angular momentum
Angular momentum and angular impulse
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Angular impulse calculations

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Problem

A boat's propeller has a rotational inertia of 4, point, 0, start text, k, g, end text, dot, start text, m, end text, squared. After a constant clockwise torque is applied for 12, start text, s, end text, the propeller's angular speed changes from a clockwise 6, point, 0, start fraction, start text, r, a, d, end text, divided by, start text, s, end text, end fraction to a clockwise 18, start fraction, start text, r, a, d, end text, divided by, start text, s, end text, end fraction.
What was the torque applied to the propeller?
Answer using a coordinate system where counterclockwise is positive.
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
start text, N, end text, dot, start text, m, end text
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