how to find initital velocity?

Question

I need to know how to find the initial velocity.
Can someone help me. I need to find the initial velocity to make an equation to graph.

The variables are:

g= (9.81 m/s2)
time= 3.5 sec
initial height = 0.20995 meters

the equation to find it is:

y= (initial velocity)(time) + (-.5)(g)(time) + (initial height)

how would i do that to solve for the initial velocity?

Answer 1

y=vt-0.5gt^2+h
If y=0, ur initial velocity is (0.5gt^2-h)/t, u just isolated vt in the right hand side of the equality, and when u plug th values in (0.5gt^2-h)/t that is (0.5 x 9.8 x 3.5squared - 0.20995) divided by 3.5, u have initial velocity equal 17.20998571m/s

Answer 2

Your equation has an error which can explain why you have gotten so many different anwers. y = v0*t - .5*g*t^2 + h0. The acceleration term must have the square of time (check the units in each term). If the initial conditions include y=0 the initial velocity is given by v0 = (.5*g*t^2 - h0)/t; this comes out 17.108 m/sec

Answer 3

In the initial position, consider h1= 0.20995 (initial height), t1=0, and v1 is what we want to find. in the final position, consider h2=0 (ground), t2= 3.5 (Time needed to travel)

your equation becomes (only changing the symbols):
h2=v1.t2 + (-5).g.t2 + h1

applying the given values:

0=3.5 v1 + (-0.5)*9.81*3.5 + 0.20995

by solving this equation, we can find that v1= 4.8450142857 m/s

Enjoy ;)

Answer 4

y=(x)(3.5)+(-.5)(9.81 m/s2)(3.5)+(0.20995 meters)

sole for x or y then put x or y back into the equasion then that will solve for x which is initial velocity its actually quite simple!!!

then you should come up with y= -16.95755x

then solve for x and y!!! but im not to sure how accurate this is though!!!!

Answer 5

you can use the equation
v= u - gt
0= u - 9.81*3.5
u= 34.335m/s

Answer 6

What is Y??