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3 years ago

11

ou are sparring in a tae kwon do class. Your opponent executes a roundhouse kick. The average angular velocity of his kicking le

g and foot is 20 rad/s. The angular displacement from his foot to your head is 5 rad. How much time do you have to move if you want to avoid being kicked in the head?

1 answer:

nordsb [41]3 years ago

6 0

Answer:

0.25 s

Explanation:

The angular velocity, <em>ω</em>, is related to the angular displacement, <em>θ</em>, by

$\omega = \dfrac{\theta}{t}$

<em>t</em> is the time.

Making <em>t</em> subject of the formula,

$t = \dfrac{\theta}{\omega}$

Substituting values in the question,

$t = \dfrac{5}{20} = 0.25\text{ s}$

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