Chapter 4 Energy, work and power Flashcards
What is work
1 Joule of work is done when a force of 1 N moves an object by 1 metre in the direction of the force
SI unit of work
Joule
Formulas for work
work done = force * distance moved in the direction of the force
work done = energy transferred
What is kinetic energy
Energy stored by an object because of its motion
What is Gravitational potential energy
Energy stored by objects lifted upwards against the force of gravity.
What is Elastic (strain) energy
Energy stored by stretched objects such as rubber bands and springs
What is chemical energy
Energy stored in chemical bonds between atoms
What is electrostatic energy
The potential energy of a system of separated electric charges.
What is nuclear energy
Energy that is released when the particles or nucleus, which is made of particles bound together by strong forces, split.
How can energy be transferred
Mechanically - forcefully moving an object
Electrically - current
Heating - temp diff
Radiation of sound and light waves
What is the conservation of energy
Can’t be created or destroyed, can only be stored or transferred
Formula for GPE
mgh
Formula for KE
1/2 mv^2
SI unit of energy
Joules (J)
What is efficiency
The amount of useful work done out of the total energy input.
