Proof that gravity equals 9.8 metres per second?

  • Thread starter Thread starter EasyTheySaid
  • Start date Start date
  • Tags Tags
    Gravity Per Proof
AI Thread Summary
To confirm that gravity equals approximately 9.8 meters per second, one can drop an object from various heights and calculate its velocity and acceleration, though this method requires eliminating air resistance for accurate results. Experiments conducted in vacuum conditions yield results closer to 9.8, as gravity also varies with latitude. Measurement errors typically overshadow the effects of air resistance unless advanced equipment is used. Traditional methods, such as using a ticker tape to measure displacement over time, can provide a first-order approximation of gravitational acceleration. Overall, while the proposed method is valid, achieving precise measurements necessitates careful consideration of environmental factors.
EasyTheySaid
5
0
If you had to confirm that gravity equals approximately 9.8 metres per second would you take an object and drop it from different heights. Would you then take the time and displacement and work out velocity and then use that to work out acceleration??

EDIT: In this example there is no air resistance
 
Last edited:
Physics news on Phys.org
the experiment won't give exactly 9.8 , since air friction is also there .
You need vacuum or vacuum like condition for 9.8 .
And g also varies with latitudes .
 
kushan said:
the experiment won't give exactly 9.8 , since air friction is also there .
You need vacuum or vacuum like condition for 9.8 .
And g also varies with latitudes .

That's why I said approximately 9.8.
Is my method correct?
 
, you need to eliminate air resistance
 
kushan said:
, you need to eliminate air resistance

Thank you
 
You're method is good enough for a first order approximation.
 
Your measurement errors will be greater then the effects of air resistance unless you have some pretty exotic equipment.

The traditional method for doing this was to fasten a strip of waxed paper tape to your weight and feed it through a sparker with a know rate. The distance between the dots give you the displacement in fixed time intervals.
 
Integral said:
Your measurement errors will be greater then the effects of air resistance unless you have some pretty exotic equipment.

The traditional method for doing this was to fasten a strip of waxed paper tape to your weight and feed it through a sparker with a know rate. The distance between the dots give you the displacement in fixed time intervals.

I understand. Like the "ticker tape"?
 
And you can also make a pendulum of a heavy mass , light spring .
Calculate its time period ( keep the amplitude small ) , and plug it in the equation of of time period , you can find g , pretty close enough .
 
  • #10
Galileo used the inclined plane.
 
Back
Top