What Is the Velocity of a Hammer Sliding Down a Roof?

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A hammer slides 2.5 meters down a roof inclined at 15 degrees, and the goal is to find its initial velocity (Vo) and the direction of its velocity at the moment it leaves the roof. The discussion highlights the challenge of translating physics problems into solvable equations, particularly with two unknowns. Key insights suggest focusing on the component of gravity acting along the incline rather than relying solely on kinematic equations. The user successfully derived the equation for Vo using gravitational acceleration and the distance traveled. Ultimately, the problem was resolved with the help of forum members.
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Good morning, first post and more than excited that I can get possible help for physics. Only problem I think I have is translating physics problems into soluble questions.

Homework Statement



A hammer slides 2.5 m down a smooth roof which has an incline of 15 degrees.

At the instant the hammer leaves the roof, find the magnitude Vo and direction of the angle of its velocity.

x = 2.5 m
angle = 15 degrees

Homework Equations



X = Xo + Vot + 1/2at^2
V^2 = Vo^2 + 2a(X-Xo)
X = Xo + 1/2(V+Vo)t

The Attempt at a Solution



Having two unknowns is leaving me at a halt. Is final velocity [at the instant leaving the roof] 0 m/s? The last equation [X = Xo + 1/2(V+Vo)t] would have V = 0 m/s and Vo = 0 m/s making the entire equation unsolvable.
 
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Welcome to PF.

You only need to determine your Vo. It is accelerated over the distance of the roof by what part of gravity? (You have the angle so figure the component of gravity that accelerated it.)

Doesn't look like you need your kinematic equations.
 
LowlyPion said:
Welcome to PF.

You only need to determine your Vo. It is accelerated over the distance of the roof by what part of gravity? (You have the angle so figure the component of gravity that accelerated it.)

Doesn't look like you need your kinematic equations.

I used the equation

V^2 = Vo^2 +2a(X-Xo)

and through algebra got

Vo = square root of 2g(X-Xo)

my question is should we reconstruct the the equation to be Vo = 2gcos15(X-Xo) in respect to the incline?

Editnm i got it! Thanks alot! =]]]
 
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