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2 years ago

A parent swings a 13.5 kg child

Physics

1 answer:

solmaris [256]2 years ago

3 0

The speed of the child is 2.21 m/s

Explanation:

The child is moving in circular motion. First of all, we find its frequency of revolution, which is given by:

$f=\frac{N}{t}$

where

N = 11 is the number of revolutions

t = 25.4 s is the time elapsed

So,

$f=\frac{11}{25.4}=0.433 Hz$

Now we find the angular frequency, which is given by

$\omega = 2\pi f = 2\pi(0.433)=2.72 rad/s$

And now we can fidn the linear speed of the child, which is given by

$v=\omega r$

where

$\omega=2.72 rad/s$ is the angular frequency

r = 0.811 m is the radius of the circular trajectory

Substituting,

$v=(2.72)(0.811)=2.21 m/s$

Learn more about circular motion:

brainly.com/question/2562955

brainly.com/question/6372960

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Explain whether there can be forces act-

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2 years ago

A swinging pendulum has a total energy of <img src="https://tex.z-dn.net/?f=E_i" id="TexFormula1" title="E_i" alt="E_i" align="a

Zolol [24]

Answer:

$\frac{E_{2}}{E_{1}} \approx 1 -\frac{3\theta}{1-\theta}$ (for small oscillations)

Explanation:

The total energy of the pendulum is equal to:

$E_{1} = m\cdot g \cdot (1-\cos \theta)\cdot L$

For small oscillations, the equation can be re-arranged into the following form:

$E_{1} \approx m\cdot g \cdot (1-\theta) \cdot L$

Where:

$\theta = \frac{A}{L^{2}}$ , measured in radians.

If the amplitude of pendulum oscillations is increase by a factor of 4, the angle of oscillation is $4\theta$ and the total energy of the pendulum is:

$E_{2} \approx m\cdot g \cdot (1-4\theta)\cdot L$

The factor of change is:

$\frac{E_{2}}{E_{1}} \approx \frac{1 - 4\theta}{1-\theta}$

$\frac{E_{2}}{E_{1}} \approx 1 -\frac{3\theta}{1-\theta}$

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3 years ago

What increases the work output of a machine

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3 years ago

A research submarine has a 20-cm-diameter window that is 9.0 cm thick. The manufacturer says the window can withstand forces up

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Answer:

The maximum safe depth in salt water is 3758.2 m.

Explanation:

Given that,

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$A=\pi\times r^2$

Put the value into the formula

$A=\pi\times(10\times10^{-2})^2$

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We need to calculate the pressure

Using formula of pressure

$P=\dfrac{F}{A}$

Put the value into the formula

$P=\dfrac{1.2\times10^{6}}{0.0314}$

$P=38216560.50\ Pa$

$P=3.8\times10^{7}\ Pa$

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Using equation of pressure

$P=P_{atm}+\rho gh$

$h=\dfrac{P-P_{atm}}{\rho g}$

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2 years ago

In the nuclear fission process mass is converted into energy. Determine the total mass that must be converted to energy in one y

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Answer:

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Part 2)

At 30% efficiency the mass converted equals

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3 years ago