5.1a Measured quantities can be classified as either vector or scalar.

5.1b A vector may be resolved into perpendicular components.*

5.1c The resultant of two or more vectors, acting at any angle, is determined by vector

addition.

5.1d An object in linear motion may travel with a constant velocity* or with acceleration*.

(Note:Testing of acceleration will be limited to cases in which acceleration is constant.)

5.1e An object in free fall accelerates due to the force of gravity.*Friction and other

forces cause the actual motion of a falling object to deviate from its theoretical motion.

(Note: Initial velocities of objects in free fall may be in any direction.)

5.1f The path of a projectile is the result of the simultaneous effect of the horizontal and

vertical components of its motion; these components act independently.

5.1g A projectile ’s time of flight is dependent upon the vertical components of its motion.

5.1h The horizontal displacement of a projectile is dependent upon the horizontal com-

ponent of its motion and its time of flight.

5.1i According to Newton ’s First Law, the inertia of an object is directly proportional to

its mass. An object remains at rest or moves with constant velocity, unless acted upon by

an unbalanced force.

5.1j When the net force on a system is zero, the system is in equilibrium.

5.1k According to Newton ’s Second Law, an unbalanced force causes a mass to accelerate*.

5.1l Weight is the gravitational force with which a planet attracts a mass*.The mass of

an object is independent of the gravitational field in which it is located.

5.1m The elongation or compression of a spring depends upon the nature of the spring

(its spring constant)and the magnitude of the applied force.*

5.1n Centripetal force* is the net force which produces centripetal acceleration.*In uni-

form circular motion, the centripetal force is perpendicular to the tangential velocity.

5.1o Kinetic friction* is a force that opposes motion.

5.1p The impulse * imparted to an object causes a change in its momentum*.

5.1q According to Newton ’s Third Law, forces occur in action/reaction pairs. When one

object exerts a force on a second, the second exerts a force on the first that is equal in

magnitude and opposite in direction.

5.1r Momentum is conserved in a closed system.*(Note: Testing will be limited to momen-

tum in one dimension.)

5.1s Field strength* and direction are determined using a suitable test particle.(Notes:

1)Calculations are limited to electrostatic and gravitational fields.2)The gravitational field near the surface of Earth and the electrical field between two oppositely charged parallel plates are treated as uniform.)

5.1t Gravitational forces are only attractive, whereas electrical and magnetic forces can

be attractive or repulsive.

5.1u The inverse square law applies to electrical* and gravitational* fields produced by

point sources.