Chapter 1: Energy And Energy Resources Flashcards
How can energy be stored?
In a variety of different energy stores
What are the different ways energy is transferred?
It can be transferred via heating, waves, an electric current or by moving an object
What happens to an objects energy stores when it is dropped?
The object will gain speed when it is dropped, its store of GPE decreases and its store of kinetic energy increases
What happens when an object hits the ground?
Its kinetic energy store decreases, some or all of its energy is transferred to the surroundings, the thermal energy store of the surrounding increases, energy is also transferred by sound waves
Can energy be created or destroyed?
No
What is conservation of energy?
The conservation of energy says that energy cannot be created or destroyed
What is a closed system?
A closed system is a system in which no energy transfers take place out of or into the energy stores of the system.
Describe the movement of energy between energy stores
Energy can be transferred between energy stores within a closed system. The total energy of the system is always the same, before and after any transfers
When is work done on an object?
Work is done when a force makes the object move.
The energy transferred = Work done
Equation for work done with units
Work done (W)[joules] = force applied (F)[newtons] + distance moved(s)[meters]
How does work done affect friction?
Work done to overcome friction is transferred as energy to the thermal energy stores of the objects that rub together and the surroundings
Is work done equal to energy transferred
Yes
Energy transferred = the work done
How does the GPE of an object change when you move it up and down?
The GPE store of an object increases when it moves up
It decreases when it moves down
How is the GPE stores of an object affected when its lifted?
The GPE store of an object increases when it is lifted because work is done to overcome the gravitational force.
How is the GPE strength different on the moon than on earth
The GPE field strength at the surface of the moon is less that of earth
