How far will this bullet drop in 3 seconds

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SUMMARY

The discussion focuses on the physics of projectile motion, specifically analyzing the drop of a bullet fired horizontally from a height of 100 meters with an initial speed of 850 meters per second. The correct calculation for the bullet's vertical drop in 3 seconds, neglecting air resistance, is 44.1 meters, derived from the formula for free fall. Additionally, the discussion addresses the vertical component of a ball's velocity when kicked at a 30-degree angle, clarifying that this component decreases due to gravitational acceleration. The key takeaway is the distinction between horizontal and vertical motion in projectile dynamics.

PREREQUISITES
  • Understanding of basic physics concepts, particularly projectile motion.
  • Familiarity with kinematic equations, including displacement and velocity components.
  • Knowledge of gravitational acceleration, typically approximated as 9.81 m/s².
  • Ability to perform trigonometric calculations, specifically sine functions for angle components.
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  • Study the kinematic equations for projectile motion in detail.
  • Learn about the effects of air resistance on projectile trajectories.
  • Explore the concept of vector decomposition in physics.
  • Investigate real-world applications of projectile motion in sports and engineering.
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This discussion is beneficial for physics students, educators, and anyone interested in understanding the principles of projectile motion and its applications in real-world scenarios.

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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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