The elastic potential energy of a spring is given by

where k is the spring's constant and x is the displacement with respect to the relaxed position of the spring.
The work done by the spring is the negative of the potential energy difference between the final and initial condition of the spring:

In our problem, initially the spring is uncompressed, so

. Therefore, the work done by the spring when it is compressed until

is

And this value is actually negative, because the box is responsible for the spring's compression, so the work is done by the box.
Answer:
<h2>
128.61 Watts</h2>
Explanation:
Average power done by the torque is expressed as the ratio of the workdone by the toque to time.
Power = Workdone by torque/time
Workdone by the torque =
= 
I is the rotational inertia = 16kgm²



To get the angular acceleration, we will use the formula;


Workdone by the torque = 16 * 1.28 * 12.56
Workdone by the torque = 257.23 Joules
Average power done by the torque = Workdone by torque/time
= 257.23/2.0
= 128.61 Watts
Answer: Work W = 0
Explanation: Work W = F·s. Because rock does not move, s = 0 and
work done is zero.
For number 11, you should say that there is more pollution and fossil fuels being burned.
The Mercury's mass for the given acceleration due to gravity is 0.3152 x 10²⁴ kg.
The ratio of the calculated and accepted value of the Mercury's mass is 0.95.
<h3>What is mass?</h3>
Mass is the amount of matter present in the object.
The mass of the object is always constant, anywhere it is on the Earth or Moon or any other planet.
Given is the acceleration due to gravity of Mercury planet at North pole is g = 3.698 m/s² and the radius of Mercury planet is 2440 km.
The acceleration due to gravity is related with mass as
g = GM/R²
Substitute the values, we have
3.698 = 6.67 x 10⁻¹¹ x M/(2440 x1000)³
M = 2.2016 x 10¹³ / 6.67 x 10⁻¹¹
M = 0.3152 x 10²⁴ kg
Thus, the mercury's mass is 0.3152 x 10²⁴ kg.
(b) Accepted value of Mercury's mass is 3.301 x 10²³ kg
Ratio of the value of mass calculated and accepted is
Mcalc/M accep = 0.3152 x 10²⁴ kg / 3.301 x 10²³ kg
= 0.95
Thus, the ratio is 0.95
Learn more about mass.
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