Physics 2 Flashcards
Newton’s second law
The acceleration of an object is:
- directly proportional to the resultant force on an object
- inversely proportional to the mass of an object
Force (N)=
Mass (kg)*acceleration (m/s2)
The weight of an object is the force of gravity acting on the object
Weight (w)=
Mass (kg)*acceleration due to gravity (m/s2)
Terminal velocity:
The maximum velocity that an object can travel at in a fluid
Hooke’s law:
Force is directly proportional to extension provided the elastic limit is not reached
Total stopping distance=
Thinking distance+braking distance
Braking distance:
How far the car travels once the breaks have been applied
Thinking distance
How far the car travels during your reaction time
Thinking distance factors:
Distractions, age, alcohol consumption, drugs, tiredness
Braking distance factors:
Tyre condition, driving surface, road conditions
Both factors of braking and thinking distance:
Speed, heavy rain
Momentum
A property of a moving object which depends on how much mass the object has and how fast it is moving
P (kg m/s)=
m mass (kg)*v volume (m/s)
Conservation of energy:
Energy cannot be created or destroyed, but can only be transferred from one energy store to another energy store
Kinetic
Moving objects
Chemical
Inside chemical bonds
Thermal
Hot objects
Gravitational potential:
Lifting something up
Magnetic
Between two magnets
Elastic potential
Stretched object
Nuclear
Nuclear reactions
Mechanical
When a force is involved
Electrical
When electricity is involved
Heating
When there is a change in temperature
Radiation
By light or other EM waves
Work done
Work is done when a force moves an object through a distance
Work done is the same as the transfer of energy
Calculating work done
Work is done when a force moves an object through a distance work done(J)W=F force(N)*S distance (m)
Work done:
- Climbing a flight of stairs
- swimming
- running 100m
- turning the pages of a book
- a falling parachutist
- playing a video game
- lifting a weight
- writing on a book
No work done
- Watching TV
- a spacecraft moving at a steady speed towards the moon
- reading a book
- driving at a steady speed on a motorway
- talking
- sleeping, sitting
- holding a book
Weight
The weight of an object is the force of gravity acting on the object
