How far will this bullet drop in 3 seconds

AI Thread Summary
A bullet fired horizontally from a 100-meter tall building at 850 meters per second will drop approximately 44.1 meters in 3 seconds, as the calculation focuses on vertical displacement rather than horizontal distance. The discussion highlights the importance of understanding the difference between horizontal and vertical motion in projectile problems. For the second scenario, a ball kicked at a 30-degree angle with an initial velocity of 5.0 meters per second has a vertical component that decreases as it rises due to gravity, contrary to the initial assumption that it increases. The correct interpretation involves recognizing that vertical velocity diminishes until the peak of the trajectory. Overall, the thread emphasizes the significance of analyzing vertical displacement and velocity components in projectile motion.
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1. A bullet is fired horizontally from the roof of a building 100. meteres tall with a speed of 850 meters per second. Neglecting air resistance, how far will the bullet drop in 3.00 seconds?
1) 29.4 m 2) 44.1 m 3) 100. m 4) 2,550
Since the horizontal speed should be constant throughout, so I think 850 is the horizontal initial speed, so I did: 850*3=2550 m, but it's the wrong answer.

2. A ball is being kicked by a foot and rising at an angle of 30 from the horizontal. The ball has an initial velocity of 5.0 meters per second. As the ball rises, the vertical component of its velocity 1) decreases 2) increases 3) remains the same
I think it increases because the vertical component is 5*sin30=2.5, and once the angle increases, then it's 5*sin 45=3.54. So it obviously increased, but the answer is 1) decreases, so I don't know.

Thanks a lot for help.
 
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hint for number one
it's asking how far the bullet dropped, so find its y displacement, not x...

hint for number two
if the ball's velocity continued to increase it wouldn't come back down...also your velocity should look like V = Vosin@ - 1/2gt^2
hope this helps
 
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