A worker drops a wrench from the top of a tower 62.9 m tall. What is the velocity when the wrench strikes the ground? The acceleration of gravity is 9.81 m/s^2

Question

A worker drops a wrench from the top of a tower 62.9 m tall. What is the velocity when the wrench strikes the ground?  The acceleration of gravity is 9.81 m/s^2

joannablackwelder · Answer

v^2 = vi^2 +2ax where v is final velocity, vi is initial velocity, a is acceleration, and x is displacement.

joannablackwelder · Answer

Solve for v.

anonymous · Answer

Yes. You can view it as 
kinetic energy gained = potential energy lost

1/2 m v^2 = m g h 

g = gravity and h = height from which it fell.

This is equivalent to Joanna's equation, just explained a bit more.

anonymous · Answer

PE=KE, Mgh=$$Mgh=\frac{ 1 }{ 2 }Mv ^{2} =>v=\sqrt{2gh}=\sqrt{2*9.81*62.9}=42.69m/s $$

anonymous · Answer

Use Joanna's eqn, set $$v _{i} = 0$$, finish it off!