Projectile question - X and Y direction

AI Thread Summary
A bullet fired at a 60° angle with an initial velocity of 200 m/s has its horizontal and vertical components calculated as Vix = 100 m/s and Viy = 173.2 m/s. The time the bullet remains in the air is determined using the equation Y = (Viy)t - (1/2)at², where a = -9.8 m/s. Assuming the bullet is fired from ground level, the solution indicates that the bullet is in the air for 35.4 seconds. However, the problem's accuracy depends on the assumption of a flat landscape and the initial vertical position. Clarification on these conditions is essential for a definitive answer.
anthony123456
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A bullet is fired at an angle of 60° with an initial velocity of 200 m/s. How long is the bullet in the air?

Homework Equations



Vix = Vicosθ
Viy = Visinθ

Vfy = Viy + ayΔt
Xf = xi + VixΔt

... Ask for more equations available...

The Attempt at a Solution



Vix = 200cos60° = 100m/s
Viy = 200sin60° = 173.2 m/s

X variables:
xi = 0m
xf = ?
Δt =?
Vix = 100m/s


Y variables:
Yi = ?
Yf = 0m
Δt =?
Viy = 173.2m/s
Vfy = ?
a = -9.8m/sANSWER HAS TO EQUAL 35.4 SECONDS, ACCORDING TO MY PHYSICS TEACHER!
 
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Relevant Equation
Y=(V_{iy})t-\frac{1}{2}at^2
 
The question is unanswerable, because you are not given knowledge about the initial y-component position of the bullet or the landscape into which the bullet will travel.

But if we assume your teacher meant to describe a world in which bullets are fired from ground level into landscapes that are perfectly flat, we can proceed. If that is the case, Yi = 0. If you need additional help, just ask for it.
 
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