As we know by work energy theorem
total work done = change in kinetic energy
so here we can say that wok done on the box will be equal to the change in kinetic energy of the system

initial the box is at rest at position x = x1
so initial kinetic energy will be ZERO
at final position x = x2 final kinetic energy is given as

now work done is given as

so we can say

so above is the work done on the box to slide it from x1 to x2
Answer:
Rechargeable batteries can still go flat after repeated use because the materials involved in the reaction lose their ability to charge and regenerate
Explanation:
they go flat because they a rechargeable and sometimes don't always work
thank you hope u have a good day
The second statement is false. The Sun is a star, but not the only star.
Using the idea of motion under gravity, it will take 0.5 seconds more before the phone hits the ground.
<h3>What is the distance covered?</h3>
The distance covered is obtained form the equations of kinematics under gravity.
Now;
v = u + gt
Recall that it was dropped from a height hence u = 0 m/s
v = gt
v = 9.8 m/s^2 * 4 s
v = 39.2 m/s
Now;
h = ut + 1/2gt^2
but u = 0 m/s
h = 1/2gt^2
h = 1/2 * 9.8 * (4)^2
h = 78.4 m
The phone will not hit the ground within this time
For the phone to hit the ground;
h = 1/2gt^2
if h = 100 m
100 = 1/2 * 9.8 * t^2
2 * 100/9.8 = t^2
t = √2 * 100/9.8
t = 4.5 seconds
It will take about 0.5 seconds more before the phone will hit the ground.
Learn more about motion under gravity:brainly.com/question/15120445
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