List of top Science Questions on Energy

The correct statements are:
A. Energy payback time (EPBT) should be less than life of PV System
B. Life cycle conversion efficiency (LCCE) should be less than one
C. Energy production factor (CEPF) on life time basis should be more than one
D. Carbon emission is more if electrical power is generated by PV in comparision to the electrical power generated by conventional power plant
Choose the correct answer from the options given below:
A battery lights a bulb. Describe the energy changes involved in the process.
The potential energy of a freely falling object decreases progressively. Does this violate the law of conservation of energy? Why?
What are the various energy transformations that occur when you are riding a bicycle?
Does the transfer of energy take place when you push a huge rock with all your might and fail to move it? Where is the energy you spend going?
A certain household has consumed \(250\) \(units\) of energy during a month. How much energy is this in joules?
An object of mass \(40\) \(kg\) is raised to a height of \(5\) \(m\) above the ground. What is its potential energy? If the object is allowed to fall, find its kinetic energy when it is half-way down.
Find the energy in joules consumed in 10 hours by four devices of power 500 W each.
A freely falling object eventually stops on reaching the ground. What happenes to its kinetic energy?
An electric heater is rated 1500 W. How much energy does it use in 10 hours?
Illustrate the law of conservation of energy by discussing the energy changes which occur when we draw a pendulum bob to one side and allow it to oscillate. Why does the bob eventually come to rest? What happens to its energy eventually? Is it a violation of the law of conservation of energy?