What is the velocity of a body thrown into a pit?

[chawki]

Homework Statement

A body is thrown vertically upward from the distance h = 1,5 m above the ground at the
edge of a pit having a depth of s = 3,5 m. The initial velocity of the body is 2,3 m/s.

Homework Equations

Determine the velocity at which the body will reach the bottom of the pit.

The Attempt at a Solution

(h=5m)

V²-V₀²=2gh
V=10.168 m/s

 

[flyingpig]

What a violent problem...

I'll give you a hint, the initial height is 1.5m, but the total height is 3.5m.

 

[chawki]

What a violent problem...

I'll give you a hint, the initial height is 1.5m, but the total height is 3.5m.

really ?

 

[Doc Al]

The Attempt at a Solution

(h=5m)

V²-V₀²=2gh
V=10.168 m/s

Looks good.

 

[chawki]

Hello Doc Al, Thank you for your help on the last time regarding equations..i try not to mess up my mind with them.

regarding this actual problem, I'm starting to think that flying pig is right :/

 

[Doc Al]

regarding this actual problem, I'm starting to think that flying pig is right :/

Why is that?

 

[flyingpig]

Take Doc Al's advice. I just glanced over the problem and your equation. I just saw that you missed the initial height in your equation, so I jumped into a conclusion lol

 

[chawki]

Take Doc Al's advice. I just glanced over the problem and your equation. I just saw that you missed the initial height in your equation, so I jumped into a conclusion lol

ahaa..lol don't confuse me I'm easy to confuse :shy:
i'm glad i was right at the first try

 

[chawki]

This is how I'm imagining it...

 

[chawki]

Am i right ?

 

[Doc Al]

Am i right ?

Yes.

 

[chawki]

Yes.

Thank you

 

[killme22]

i think you're right boy .. here's my solution

v^2 = Vo^2 - 2gy
Vo=2.3m/s
y=1.5+3.5 = 5m

V=2.3^2 -2(9.8)(-5)
V=10.16m/s downward ..