Chapter 1 - Energy Flashcards
What is energy
energy is the capacity to do work
What is kinetic energy
it is the energy which a moving object have
It depends on the speed of the object
what is the S.I unit for energy
Joules ( J )
If the object is moving
there will be kinetic energy
if the object is stationary
there is no kinetic energy
faster the object moves
the more kinetic energy it has
what is gravitational potential energy ?
it is the energy that an object has because of its position
It also depends on the position of the object
What is potential energy
It is stored energy
what is elastic potential energy?
it is stored in objects that can be stretched , compressed or bent
what is chemical potential energy
it is the energy stored in substances such as fuels and food
What are the 3 types of potential energy
elastic, gravitational and chemical
what is thermal energy
thermal energy is the energy of an object has become because of its temperature
It depends on the temperature of the object
thermal energy travels from….
from a region of a higher temperature of a lower temperature
what are the principals of energy
energy cannot be created or destroyed and energy can be changed from one form to another
what is the energy conversion when lighting a bulb with a battery
chemical energy - electrical energy - light + heat energy
what is the energy conversion when shooting an arrow with a bow
elastic potential energy - kinetic energy
why should we conserve energy
conserving energy can reduce the amount of energy used
what is the energy conversion when charging our mobile devices
electrical energy - chemical potential energy
what are some ways we can conserve / save energy
- switch off all electrical appliances when not in use
- use the fan instead of air-conditioning
- Use the public transport instead of driving
what is power
it is the rate at which energy is used or conserved
for example , hakim climbs up the ladder within 10 seconds while ben climbs up the ladder within 20 seconds. who has more power?
Hakim will have more power as he gains the same amount of gravitational energy in a shorter time
what is the S.I unit for power
Watts ( W )
what is the formula for power
Energy ( J ) ÷ time ( seconds )
what is the formula for energy
Power ( W ) × Time ( S )
what is the formula for time
Energy ( J ) ÷ Power ( W )
