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3 years ago

11

A hockey puck is at rest on a flat surface. Then one end of the surface is lifted gradually, forming an inclined plane of increa

sing slope. By measuring the angle of the slope at which the puck begins to slide, what quantity can be calculated?
the coefficient of kinetic friction between the puck and the surface

the mass of the puck

the volume of the puck

the coefficient of static friction between the puck and the surface

2 answers:

Jlenok [28]3 years ago

6 0

The coefficient of static friction between the puck and the surface.

In fact, that coefficient describes exactly how "hard" it is to cause the puck to start moving, if it starts from an idle condition.

ikadub [295]3 years ago

6 0

Answer:

the coefficient of static friction between the puck and the surface

Explanation:

As per the FBD we can say that as we increase the angle of the inclination the component of force of gravity will counterbalance the friction force

At the condition of just equilibrium when it is just begin to slide then in that case we can say

$F_f = mg sin\theta$

so here for finding frictional force maximum value we can say

$F_f = \mu F_n$

here for finding Normal force we can write force balance normal to the inclined plane

$F_n = mgcos\theta$

now from above equations

$\mu (mgcos\theta) = mg sin\theta$

$\mu = tan\theta$

so angle depends on the coefficient of static friction

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