Projectile Motion — How far from the gun does the bullet land?

AI Thread Summary
The discussion centers on understanding how to connect the horizontal (x) and vertical (y) components of projectile motion when calculating the distance a bullet lands from the gun. It emphasizes that, in the absence of air resistance, the two components can be treated independently. The vertical motion is affected by gravity, while the horizontal motion remains constant. Participants suggest using time to find when the bullet hits the ground and then applying that to the horizontal distance. Overall, the key takeaway is that the x and y components should not be directly linked, but rather analyzed separately to solve the problem effectively.
Tinkylo
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Homework Statement
The bullet fired from a gun on the ground has a velocity v. The x-component of the velocity is 8.4 ms-1 and the y-component of the velocity is 9.2 ms-1. x is the horizontal axis and y is the vertical axis. What is the distance in m between the gun and the point where the bullet hits the ground? Acceleration due to gravity is 9.8ms-2. Assuming there is no air resistance during the bullet's flight.
Relevant Equations
Not sure
I don't know how to link the x-component and y-component together.
 

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Tinkylo said:
I don't know how to link the x-component and y-component together.
Distance, start velocity, final velocity, time, acceleration. For which does the same value apply to both coordinates?
 
Tinkylo said:
I don't know how to link the x-component and y-component together.
As there is no air resistance, the vertical and horizontal components of velocity are not linked in the problem.Consider the problem as independent horizontal and vertical motions.
 
Tinkylo said:
Relevant Equations:: Not sure

I don't know how to link the x-component and y-component together.
Don't link those, they are giving you the vertical and horizontal components of the initial velocity in order to facilitate the problem.
Hits:
Purely vertical movement: decelerated while moving up / stop / accelerated while falling down.
Purely horizontal movement: non-accelerated and lasting as much as the up-down vertical movement.
 
Lnewqban said:
Don't link those
It's not clear what @Tinkylo means by linking them. My interpretation is finding something that links the horizontal and vertical equations. See my hint in post #2.
 
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Tinkylo said:
Homework Statement:: The bullet fired from a gun on the ground has a velocity v. The x-component of the velocity is 8.4 ms-1 and the y-component of the velocity is 9.2 ms-1. x is the horizontal axis and y is the vertical axis. What is the distance in m between the gun and the point where the bullet hits the ground? Acceleration due to gravity is 9.8ms-2. Assuming there is no air resistance during the bullet's flight.
Relevant Equations:: Not sure

I don't know how to link the x-component and y-component together.
You can work it out from first principles from the equations for x and y as a function of t (time). This involves finding the value of t when y = 0 and then using that value of t in the equation for x. Or you can use the relationship between range, velocity and launch angle that you may have been given: ##R = \frac{v_0^2 \sin{2\theta}}{g}##. If you use this relationship, you will have to find ##v_0## and the launch angle. Which method do you wish to use?

AM
 
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