what formula to use for finding decrease in velocity

[staceyrho]

I am not sure which of the many formulas to solve my problem to use:

Given: The acceleration of gravity on Earth is 9.8 m/s^2

Consider a ball thrown up from the ground (the point 0). It passes a window (the segmenta AB) in the time interval 0.233 s. The distance AB is 1.29m. What is the magnitude of the decrease of the velocity from A to B? Answer in units of m/s.

Can anyone tell me what formula to use to solve this?

 

[TchrWill]

Re: I need help with what formula to use

Given: The acceleration of gravity on Earth is 9.8 m/s^2.

Consider a ball thrown up from the ground (the point 0). It passes a window (the segmenta AB) in the time interval 0.233 s. The distance AB = 1.29m.

What is the magnitude of the decrease of the velocity from A to B?

h = Vot - (gt^2)/2 will give you the initial velocity at time zero.
Vo = initial velocity, t = time and g = 9.8m/sec^2.

Having the initial velocity, Vo, The velocity at time t = .233 sec and h = 1.29m derives from Vf = Vo - gt where Vf = the velosity at tme t = .233 sec and h = 1.29m.

I'll let you work out the answer for your numbers.

I get a velocity decrease from A to B of 2.2834m/s