Acceleration due to gravity

How to determine g=9.8m/t*t

Now I have two methed

Methed 1

• G=weight/mass

• To measure weight we can use newton meter or spring balance

To measure mass we can use common balance

a)two pan balance

b)moment balance

But it is not a good methed

Methed 2

• g=4π *πh/ t*tMeasure h we can use rule Measure t we can use stop watchThen we should draw table with L/m time for 20 oscillation/s T=t/20/sl/T*T

picture• The picture

graph

gradient=L/T*T

g=4π*π*the gradient

errors

• Air resistance will cause T get small g will get big

• Reading the number of L too samll(big) g will get small(big)