Help with physics kinamatics??

Question

ok so we are doing an experiment in which we used meter sticks, a timer, and a boncy ball to find gravity. We timed how long it took the ball to drop from the celing to the floor at different distances. Then we are supposed to find the accelaration and figure out the gravity from there. Here is an example:

Time: 0.81sec Distance 3 meteres Acceleration 0.10935

i did that many times and found the average acceleration for each different trail (different lenghts and stuff) Now i need to find gravity, so what do i do??? someone said to plug it into d=vt + 1/2atsquared. Help please :)

Answer 1

ya thats the equation you have to use. because the others wont work

because remember your a can be your g

Answer 2

looks like you already found acceleration? you said .10935! that would be gravity, but that is a mistaken acceleration. i dunno what its supposed to be

if you plug it into that formula, you get 3=1/2(a)(.81)^2=(0)(.81)

(v is 0 because its initial velocity)

solving for a gets you acceleration=9.145m/s

this makes your gravity 9.145m/s^2

it is actually closer to 9.8m/s^2, but you are pretty close!

make it a good day

Answer 3

Your working formula is

D = VT + (1/2)(a)T^2

where

D = initial height at which ball was released

V = initial velocity = 0 (since ball was released)

a = acceleration due to gravity

T = time for ball to reach the floor after release

Since V = 0, the above equation simplifies to

D = (1/2)(a)(T^2)

and solving for "a",

a = 2D/T^2

The "a" in this case is the acceleration due to gravity. This is what you are looking for in your experiment. If your measurements are fairly accurate, the value of "g" should be around 9.8 m/sec^2.

I do not understand how you got an acceleration of 0.10935 (based on your given figure above).