Finding time and final velocity

AI Thread Summary
The problem involves a camera dropped from a helicopter ascending at 12.5 m/s from a height of 60 m. The correct initial velocity of the camera is 12.5 m/s, not 0, as it retains the helicopter's speed upon release. Using the equations of motion, the time it takes for the camera to reach the ground is calculated to be approximately 3.5 seconds, and the final velocity upon impact is around 33.67 m/s. The discussion emphasizes the importance of considering the initial velocity when solving projectile motion problems. Accurate calculations require recognizing the initial conditions of the object's motion.
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Homework Statement


A photographer in a helicopter ascending vertically at a constant rate of 12.5 m/s accidentally drops a camera out the window when the helicopter is 60.0 m above the ground.
-How long will it take the camera to reach the ground? What will its speed be when it hits?
a= -9.8 m/s^2 displacement=60 m

Homework Equations


(final v)^2=(initial v)^2 + 2*a*deltax
deltax=1/2a(t^2)+(initial v*t)



The Attempt at a Solution


initial v=0
so time will equal 3.5 s, and final velocity will equal 33.67 m/s^2
however, these are incorrect
 
Physics news on Phys.org
The initial v is not 0, but the v of the helicopter and photographer. If you don't believe is, look up some movies of a ball shot from a moving car: when the car is moving at 50 km/h and the ball is shot backwards at 50 km/h, it drops straight down.
 

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