AS Level Physics Definitions Flashcards
(69 cards)
Scalar
A quantity that has a magnitude only.
vector
A quantity that has both magnitude and direction.
precision
the measurements have a small range
accuracy
The closeness of measurement values to the true values.
systematic error
The type of error that causes readings to deviate in one direction from the true value.
random error
The type of error which causes readings to scatter about the true value.
distance
Total length covered irrespective of the direction of motion.
displacement
Distance moved in a certain direction from start to end point.
speed
Distance travelled per unit time.
velocity
The rate of change of displacement.
acceleration
The rate of change of velocity.
mass
A property of a body that resists change in motion.
linear momentum
The product of mass and velocity.
force
The rate of change of momentum.
Newton’s First Law
A body continues in a state of rest or constant velocity unless acted upon by a resultant force.
Newton’s Second Law
The resultant force is equal to the rate of change of momentum and acts in the direction of it.
Newton’s Third Law
Every action has an equal and opposite reaction.
Impulse
The product of the force and the time during which the force acts.
Weight
The effect of gravitational field on a mass.
Principle of conservation of momentum
For a system of interacting bodies, the total momentum remains constant provided there is no resultant force acting on the system.
Elastic collision
Both momentum and kinetic energy are conserved.
Inelastic collision
Only momentum is conserved; total kinetic energy is not conserved.
moment
The product of the force and the perpendicular distance of its line of action to the pivot.
torque of a couple
The product of one force in a couple and the perpendicular distance between the forces.