Zusammenfassung der Ressource
Physics Forces and their Effects
- Resultant Forces
- A stationary object remains stationary
if the sum of the forces acting upon it -
Resultant Force - is Zero
- If the resultant force is not zero
the object will start to accelerate,
in the same direction as the force
- The acceleration depends on the force
applied, and the mass of the object
- An object may have several different
forces acting upon it, which can have
different strengths and directions.
- When all the forces are balanced,
the resultant force is zero. in this
case: a stationary object remains
stationary and a moving object
keeps on moving at the same
speed in the same direction
- Force Mass and Acceleration (F = M x A)
- Objects accelerate when the
resultant force is not zero and
their are factors including mass
and speed which affect variables
- An object will accelerate in the
direction of the resultant force. The
bigger the force, the greater the
acceleration. Doubling the size of
the force, doubles the acceleration
- An object will accelerate in the
direction of the resultant force. a
force on a large mass will
accelerate it less than the same
force on a smaller mass. Doubling
the mass halves the acceleration
- Forces and Motion
- The gradient of a
distance time
graph represents
the speed of an
object
- The velocity of an object is its
speed in a particular direction.
The slope on a velocity time
graph represents the
acceleration of an object
- When an object moves in a
straight line with a constant
acceleration, you can calculate
its acceleration if you know
how much its velocity changes
and how long this takes
- Forces and Breaking
- The stopping distance of a car depends
on two factors: - Thinking distance and
breaking distance. Under normal driving
conditions, the thinking and breaking
distance depend on the speed of the car.
- When a vehicle travels at a steady speed
the driving force from the engine is balances
by the air resistance and other resistive
forces. The resultant force is zero.
- It takes time for a driver to
react to a situation and start
to apply the breaks. The car
carries on moving during this
reaction time.
- The thinking distance is the distance travelled
in the reaction time, The thinking distance
increases if the reaction time increases. This
can happen if the driver is: Tired, Distracted,
Under the influence of drugs or alcohol.