Posted by **James** on Friday, May 18, 2012 at 1:08pm.

An object is thrown vertically and has an upward velocity of 5 m/s when it reaches three fourths of its maximum height above its launch point. What is the initial (launch) speed of the object?

- Physics -
**bobpursley**, Friday, May 18, 2012 at 3:50pm
total energy at beginning=totalenergy at point above

1/2 m vi^2=1/2 m 5^2+mg(3/4 h)

this indicates that you have two variables, height, and velocity initially.

but we know in the final 1/4 h, vf=0, and

Vf^2=Vi^2+2gd

0=25-2*9.8*h/4

or h=50/9.8

now you can solve for vi in the first equation.

## Answer this Question

## Related Questions

- Physics - An object is thrown vertically and has an upward velocity of 5 m/s ...
- Physics - An object is thrown vertically and has an upward velocity of 18 m/s ...
- physics - An object is thrown vertically upward such that it has a speed of 56 m...
- Physics - An object is thrown vertically upward such that it has a speed of 32 m...
- physics - In the absence of air resistance two balls are thrown upward from the ...
- Physics - A ball is thrown straight upward and rises to a maximum height of 20 m...
- Physics - A ball is thrown straight upward and rises to a maximum height of 23 m...
- physics - A ball is thrown straight upward and rises to a maximum height of 14.6...
- Physics - A ball is thrown straight upward and rises to a maximum height of 16 m...
- NU - a ball is thrown straight upward with some unknow velocity. The ball ...