Energy: Forces Doing Work Flashcards
1
Q
What is a system?
A
- A single object or a group of objects
2
Q
What changes are involved in the way energy is stored when systems change?
A
- Energy is transferred
- to or away from the system
- Between different objects in the system or different types of energy stores
- Some energy is dissipated
3
Q
What happens to the energy in a closed system?
A
net change of energy is zero
4
Q
What are the ways in which energy can be changed?
A
- Work done
- Electrical equipment
- Heating
5
Q
What is work done?
A
Energy required to move an object a certain distance
Energy transferred = work done
6
Q
How do you measure the work done?
A
E = F x d
7
Q
what is the formula for GPE
A
∆GPE = m x g x ∆h
8
Q
kinetic energy formula?
A
1/2 * m * v^2
9
Q
When do mechanical processes get wasteful?
A
- when they cause a rise in temperature
- energy is lost to the surroundings
10
Q
What is power?
A
- Rate of energy transfer
- Measured in watts
- 1 watt is 1j/s
11
Q
Formula for power?
A
- Energy transferred/time
