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svet-max [94.6K]

3 years ago

9

if you have to apply 40 n of force on a crowbar to lift a 400 n rock what is the actual machanical andvatage of the crow bar

1 answer:

Eduardwww [97]3 years ago

7 0

M.A. = 400/40

M.A. = 10

Hope this helps!

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Answer: $5.77\ rps$

Explanation:

Given

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after 17 revolution i.e. $\theta =17\ rev$

using $\Rightarrow \omega_f^2-\omega_i^2=2\alpha\theta$

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2.0 kg mass is lifted4.0m above the ground find the gravitational energy

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Under some circumstances, a star can collapse into an extremely dense object made mostly of neutrons and called a neutron star.

Vsevolod [243]

Answer:

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Explanation:

Given that,

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Equal masses of two stars $m_{1}=m_{2}$

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$\omega=\dfrac{2\pi}{T}$

Put the value into the formula

$\omega_{1}=\dfrac{2\pi}{3024000}$

$\omega_{1}=0.00207\times10^{-3}\ rad/s$

Let the initial moment of inertia of the star is

$I_{1}=m_{1}r_{1}^2$

Final moment of inertia of the star is

$I_{2}=m_{2}r_{2}^2$

From the conservation of angular momentum

$I_{1}\omega_{1}=I_{2}\omega_{2}$

$\omega_{2}=\dfrac{I_{1}\omega_{1}}{I_{2}}$

$\omega_{2}=\dfrac{m_{1}r_{1}^2\omega_{1}}{m_{2}r_{2}^2}$

Put the value into the formula

$\omega_{2}=\dfrac{(7.0\times10^{5})^2\times0.00207\times10^{-3}}{18^2}$

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Hence, The angular speed of the neutron star is 3130.5 rad/s.

8 0

3 years ago