Investigating gInvestigating gPhysics On the Road

Lesson 9

LI…Investigate free fall.Use kinematic equations to

solve problemsEvaluate the uncertainty of a

measurement

Free fall

Gravity is uniform acceleration

Galileo first proposed the idea that all objects fall with uniform acceleration.

If gravity fields produce uniform acceleration then the equations of motion can be used to analyse free fall.

Gravity accelerates all objects on Earth at a rate of 9.8 ms-2

Free Fall

If the object is “dropped” then initial velocity is zero.

If the object is projected horizontally then initial velocity is zero (in the vertical direction) – sideways makes no difference.

Vertical acceleration is produced by gravity.

v= u + at

v2 = u2 + 2as

s = ut + ½ at2

Free Fall

If u=0 a=g is uniform and

constant t2 is a function of s

s = ut + ½ at2

∆t

s

s

t2

Investigating g

Use the worksheet to investigate g using little technology and using lots.