Zusammenfassung der Ressource
Physics 2A Continued
- Work and Potential Energy
- When a force moved on
and object through a
distance, energy in
transferred and work is
done
- Work done=
Force x
Distance
- Gravitational
Potential Energy
is energy due to
height
- Gravitational
Potential Energy =
Mass x Gravitational
Field x Height
- Kinetic Energy
- Kinetic Energy is energy of
movement
- Kinetic
Energy = 1/5 x
Mass x Speed
- Kinetic Energy
transferred is
work done
- 1/2mv = F x d
- Falling objects
convert Ep into Ek
- Forces and Elasticity
- Work done to an Elastic
object is stored as
Elastic Potential Energy
- Extension of an Elastic
object is Directly
Proportional to Force
- Force = Spring
Constant x
Extention
- But it stops working
when the force is too
great
- There is a maximum force
that the Elastic object can
take and still extend
proportionally
- Power
- Power is the 'Rate of doing
work' - i.e How much per
second
- Power = Work done /
Time Taken
- Power is measured in Watts (J/s)
- Calculating the power output is either
the amount of Kinetic Energy gained or
the amount of Potential Energy gained
- Momentum and Collisions
- Momentum = Mass x Velocity
- Momentum is the
property of moving
objects
- The greater the Mass of an object
and the greater the Velocity, the
more Momentum the object has
- Momentum
before =
Momentum
after
- Forces
cause
changes in
Momentum
- A larger
force means
a faster
change of
momentum
(so a greater
acceleration)
- Static Electricity
- The build up
of Static is
caused by
Friction
- Only Electrons
move, the
negative charges
never move
- Like charges
repel, opposite
charges attract
- Charges can move easily
through Conductors
- Current and Potential Difference
- 1) Current- Rate
of flow of
electrons in a
circuit
- 2) Potential Difference- The
driving force that pushes
around the current
- 3) Resistance-
Slows down
something in
a circuit
- Total charge
through a circuit
depends on
Current and Time
- Current
= Charge
/ Time
- Potential
Difference
is the Work
Done per
unit charge
- P.D = Work
Done /
Charge
- Resistance
- Resistance
increases with
Temperature
- P.D =
Current x
Resistance
- Series Circuits
- 1) Potential
Difference is shared
- 2) Current is the
same everywhere
- 3) Resistance
adds up
- 4) Cell Voltages
add up
- Ammeters are connected in series
- Parallel Circuits
- 1) P.D is the
same across all
components
- 2) Current is shared
between branches
- Voltmeters are
connected in
parallel