A block with mass 0.5 kg is forced against a horizontal spring of negligible mass, compressing the spring a distance of 0.2 m. When released, the block moves on a horizontal tabletop for 1.0m before coming to rest. The force constant k is 100 N/m. What is the coefficient of kinetic friction between the block and tabletop

So coefficient of kinetic friction will be equal to 0.4081

Explanation:

We have given mass of the block m = 0.5 kg

The spring is compressed by length x = 0.2 m

Spring constant of the sprig k = 100 N/m

Blocks moves a horizontal distance of s = 1 m

Work done in stretching the spring is equal to

This energy will be equal to kinetic energy of the block

And this kinetic energy must be equal to work done by the frictional force

So

So coefficient of kinetic friction will be equal to 0.4081

a longitudinal wave moves energy that is to the direction of the wave’s movement. - true

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