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Chapter 2 Formulas

SI Units

(1)     Force_NET = (mass) (acceleration)                                  (1 kg) (1 ) = 1 N
                                                                                                                where m     = meters
                                                                                                                          kg    = kilograms
                                                                                                                          s      = seconds
                                                                                                                          N     = Neutons

(2)     Work = (Force) (Distance)                                            (1 N) (1 m) = 1 J
                                                                                                                where N     = Neutons
                                                                                                                          m     = meters
                                                                                                                           J     = Joules

(3)     Potential Energy_GRAVITY = (weight) (height)
                                    weight = (mass) (gravity)
                                                                                                                Where g     = 9.8 ()

                                                                                1 J = (1 kg) (1 m) (1 )
                                                                                                     Where J      = Joules
                                                                                                                kg    = kilograms
                                                                                                                m     = meters
                                                                                                                s      = seconds

Remember from (1) that (1 kg) (1) = 1 Neuton

And from (2) that (1 N) (1 m) = 1 Joules

(4) Kenetic Energy = ½ (mass) (velocity)²(1 kg) (1 m) (1 ) = 1 Joule
(5) Power =
= 1 W

Where W = Watt

(6) Energy used = (Power) (time of use)

E = (1 W) (1 hr)

Normally time is in seconds
but for this we use hours.

(7) Speed = =

S =

Newton’s 1^st Law of Motion

A body continues in a state of rest, or motion, with a constant velocity (i.e. constant
speed in a straight line), unless acted upon by an unbalanced outside force (net force)

Newton’s 2^nd Law of Motion

Acceleration of an object (change in speed and/or direction) is directly proportional
to the net force acting upon it and inversely proportional to its mass. The direction
of acceleration will be the same as the direction of the net force.

Newton’s 3^rd Law of Motion

For every action force there is an equal and opposite reaction force.