Zusammenfassung der Ressource
Newton's Laws and Momentum
- Impulse
- Area under force-time graph
= Impulse
- Ft =∆mv
- Car crashes & Crumple Zones
- Momentum
- p = mv
- kg m/s
- Vector
- Conservation of Momentum
- Explosions
- Collisions
- Elastic
- Momentum conserved
- K.E. conserved
- Inelastic
- Momentum
conserved
- K.E. lost
- IN ANY DIRECTION IN THE
ABSENCE OF EXTERNAL FORCES,
THE TOTAL MOMENTUM OF A
SYSTEM REMAINS CONSTANT.
- THE MASS OF AN OBJECT
MULTIPLIED BY ITS VELOCITY.
- Change in kinetic energy =
force × distance
- Fd = ½mv^2 - ½ mu^2
- Change in momentum =
force × time
- Ft = mv - mu
- Newton's First Law
- Force causes
acceleration
- Balanced forces
- No net (resultant) force = no
acceleration
- A FORCE IS NECESSARY TO CHANGE THE
STATE OF REST OR OF UNIFORM MOTION
IN A STRAIGHT LINE OF A BODY.
- Newton's Second Law
- THE RATE OF CHANGE OF
MOMENTUM OF AN OBJECT IS
DIRECTLY PROPORTIONAL TO THE
RESULTANT FORCE ACTING ON IT.
- The Newton
- 1N is the force that
gives a mass of 1kg an
acceleration of
1ms^-2
- F = ma, where
m is constant
- w = mg, where g is
acceleration due to
gravity = 9.81ms^-2
- F ∝ ∆p / ∆t
- Mass is inertia
- Weight is gravity
- Newton's Third Law
- WHEN BODY A EXERTS A FORCE
ON BODY B, BODY B EXERTS A
FORCE ON A THAT IS EQUAL AND
OF THE SAME TYPE, AND
OPPOSITE IN DIRECTION.
- 'Action and reaction'
- Pairs of forces
- .................................
..............................
................................
Not to scale
- The gravitational force that
the Moon exerts on the
Earth is exactly equal and
opposite to the gravitation
force the Earth exerts on the
Moon.
- Free body force
diagram to
determine resultant
force on a body