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3 years ago

7

This problem uses the same concepts as Multiple-Concept Example 17, except that kinetic, rather than static, friction is involve

d. A crate is sliding down a ramp that is inclined at an angle 30.6 ° above the horizontal. The coefficient of kinetic friction between the crate and the ramp is 0.360. Find the acceleration of the moving crate.

1 answer:

coldgirl [10]3 years ago

8 0

Answer: $1.94 m/s^2$

Explanation:

Given

inclination $\theta =30.6^{\circ}$

Coefficient of kinetic Friction $\mu =0.36$

Forces on crate is

$mg\sin \theta -f_r=ma$

$f_r=\mu mg\cos \theta$

$mg\sin \theta -\mu mg \cos \theta =ma$

$a=g\sin \theta -\mu g\cos \theta$

$a=1.94 m/s^2$

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3 years ago

Distinguish between directly proportional and inversely proportional with an example of each

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3 years ago

A copper wire and a tungsten wire of the same length have the same resistance. What is the ratio of the diameter of the copper w

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The resistivity of tungsten(ρ₂) is 5.6×10⁻⁸ ohm-m

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Given that $R_1=R_2$ and $l_1=l_2$

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$\Rightarrow\frac{ (\frac{d_1}{2})^2}{ (\frac{d_2}{2})^2}=\frac{\rho_1\frac{l_1}{\pi R_1 }}{\rho_2\frac{l_2}{\pi R_2 }}$

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$\Rightarrow( \frac{d_1}{d_2} )=\sqrt{\frac{1.68\times 10^{-8}}{5.6\times 10^{-8}}}$

$\Rightarrow( \frac{d_1}{d_2} )=\sqrt{\frac{3}{10}}$

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Therefore the ratio of diameter of the copper to that of the tungsten is

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3 years ago

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2 years ago

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