Projectile Motion/ Velocity Question

AI Thread Summary
The discussion revolves around a physics problem involving a helicopter rising vertically at 14.70 m/s and an object projected horizontally at 8.50 m/s from a height of 196.00 m. The key questions include determining when the object will reach the ground, its horizontal displacement relative to the helicopter, and its vertical velocity upon impact. Participants emphasize the importance of correctly applying kinematic equations, particularly regarding the signs of position, velocity, and acceleration. A specific equation, 9.8t² + 14.7t - 196 = 0, is mentioned as a starting point for solving the problem. Careful substitution of values into the equations is crucial for accurate results.
MAddyG
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Homework Statement



You are piloting a helicopter which is rising vertically at a uniform velocity of 14.70 m/s. When you reach 196.00 m, a large object is projected with a horizontal velocity of 8.50 m/s from the rising helicopter.


Homework Equations



a) When does the ball reach ground level?
b) Where does the ball fall horizontally relative to the helicopter’s position?
c) What is the vertical velocity when it hits the ground?

The Attempt at a Solution



9.8t(squared) + 14.7t -196 = 0
 
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You should find the time it takes to reach the ground first.
 
MAddyG said:

The Attempt at a Solution



9.8t(squared) + 14.7t -196 = 0

Welcome to Physics Forums.

It looks like you are trying to use one of the kinematic equations,

x = xo + vot + (1/2) a t2

However, the expression you wrote has some errors as written. You are on the right track, just be more careful in substituting values into the equation. In particular, think about whether certain quantities (position, velocity, acceleration) should be positive or negative.
 
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