Answer:
Explanation:
The energy stored in a spring
= 1/2 k x²
where k is spring constant and x is extension in the spring.
= .5 x 500 x .05²
= .625 J
Work done by friction = energy dissipated
= - μmg x d , μ is coefficient of friction , m is mass , d is displacement
= - .35 x 2.8 x 9.8 x .05
= - .48 J
energy of the mass when it reaches equilibrium position
= .625 - .48
= .145 J
If v be its velocity at that time
1/2 m v ² = .145
.5 x 2.8 x v² = .145
v² = .10357
v = .32 m /s
32 cm /s
Power is the RATE of use, flow, or transfer of energy.
1 watt = 1 joule PER SECOND.
The correct choice is ' <em>a</em> '.
