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It takes 275n to set a stationary 77.3 crate in motion. what is the coefficient of static friction?

2 Answers

3 votes

Answer:

0.36

Step-by-step explanation:

User Zezollo
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3 votes

Note: I'm assuming the data 77.3 is the mass of the crate.

Answer:


\mu_s =0.36

Step-by-step explanation:

The coefficient of static friction, called \mu_s is the ratio between the force needed to start moving an object above a rough surface (Fr), and the normal force the surface exerts on the object (N).


\displaystyle \mu_s =(Fr)/(N)

The normal force is numerical equivalent to the weight of the body if no other external forces are acting.


N=m\cdot g

The mass of the crate is m=77.3 Kg, thus its weight and normal force is:


N=77.3\ kg\cdot 9.8\ m/s^2


N= 757.54\ Nw

Now we calculate the coefficient:


\displaystyle \mu_s =\frac{275\cancel{N}}{757.54\cancel{N}}


\boxed{\mu_s =0.36}

User Ash Belmokadem
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