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3 years ago

A doctor counts 68 heartbeats in 1.0 minute. What are the corresponding period and frequency of the heart rhythm

Physics

1 answer:

sergejj [24]3 years ago

8 0

Answer:

$f=1.13s^{-1}=1.13Hz$

Explanation:

Hello,

In this case, a frequency stands for a rate in which some action is done per unit of time. In this case, for the heartbeat, since 68 actions (heartbeats) occur in 1.0, the frequency turns out:

$f=\frac{68}{1.0min}=68min^{-1}$

Or as most commonly used in Hz ( $s^{-1}$ ):

$f=68\frac{1}{min} *\frac{1min}{60s}=1.13s^{-1}=1.13Hz$

Best regards.

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3 years ago

A ladder 10 ft long rests against a vertical wall. If the bottom of the ladder slides away from the wall at a rate of 1.4 ft/s,

Art [367]

Answer:

$\dfrac{d\theta}{dt} =-0.233\ rad/s$

Explanation:

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$\dfrac{dy}{dt} = -\dfrac{5.6}{3}$

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3 years ago

A ball, with a mass of 5.9kg, is thrown directly upwards. It reaches a maximum height of 10m from the point at which it was rele

katrin2010 [14]

Answer:

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Explanation:

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As the ball goes up, its speed decreases, so its kinetic energy decreases and converts into gravitational potential energy. When the ball reaches its maximum height, the speed has become zero, and all the kinetic energy has been converted into gravitational potential energy, given by:

$U=mgh$

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Since we can ignore air resistance, energy must be conserved, so the initial kinetic energy must be equal to the final potential energy of the ball, so we can write:

$K=U\\\frac{1}{2}mv^2=mgh$

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3 years ago

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nikdorinn [45]

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