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Potential Energy
Potential energy lets us do work in the present to change things in the future. If energy is currency, then potential energy is money in the bank.
Details and assumptions
- The acceleration due to gravity is \(9.8~m/s^2\).
- Treat the grandfather clock as a simple pendulum.
The gravitational acceleration is \(g=10\text{ m/s}^2.\)
An object of mass \(4\text{ kg}\) initially at rest falls freely towards a huge spring that is \(100\text{ m}\) below. If the spring constant is \(k=16\text{ N/m},\) what is the maximum change in the spring's length?
Air resistance is negligible and gravitational acceleration is \(g=10\text{ m/s}^2.\)
While an object of mass \(10\text{ kg}\) drops from the edge of a \(60\)-meter-high cliff, it experiences air resistance, whose strength during the descent is constantly \(15\text{ N}.\) What is the square of the velocity with which the object hits the ground?
A meteor of mass \(m=800\text{ kg}\) enters the earth's atmosphere with a velocity of \(500\text{ m/s},\) and falls vertically toward the ground. The meteor burns while falling, and its mass decreases at a rate of \(5\text{ kg/s}.\) If the meteor falls with a constant velocity, how much gravitational potential energy will it lose during \(16\) seconds?
Note
- The height of the meteor when it enters the atmosphere is \(1000\text{ km},\)
- The gravitational acceleration is \(g=10\text{ m/s}^2.\)