Solving the Mystery of the President's Shooting - Kinematics Physics Homework

AI Thread Summary
The discussion revolves around a physics homework problem involving the shooting of a president, where a bullet grazed his thigh. Forensic evidence indicates the bullet's instantaneous velocity was 350 m/s, with an average speed of 385 m/s and an average deceleration of 45 m/s². Four suspects, A, B, C, and D, are tested with their rifles, showing varying bullet velocities over time. Participants are encouraged to calculate deceleration and analyze the data to determine which suspect could have fired the shot. The thread seeks assistance in solving the kinematics problem related to the incident.
mclj
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1PHYSICS KINEMATICS HELP?
President was shot while at home. While sitting on the sofa near the window, one bullet came through the window and grazed the president's thigh. The CID rounded up 4 suspects : A. B, C and D. All four were found with a rifle.
Forensic scientists have concluded from evidence that the instantaneous velocity of the bullet as it hits the window is about 350m/s and its average speed is about 385m/s. Also, it had an avg deceleration of about 45m/s2. Each rifle was taken to the shooting range to be tested.

suspect: time -- bullet velocity
A: 0.0 -- 600
1.0 -- 450
2.0 -- 375
3.0 -- 330
4.0 --315
5.0 -- 300
B: 0.0 -- 420
1.0 -- 240
2.0 -- 120
3.0 -- 90
4.0 -- 75
5.0 -- 55


C: 0.0 -- 420
1.0 -- .360
2.0 -- 300
3 .0 -- 240
4.0 -- 180
5.0 -- 120

D: 0 . 0 -- 600
1.0 -- 410
2.0 ---- 320
3.0 -- 230
4.0 -- 180
5 .0 -- 150

WHO SHOT THE PRESIDENT? WHY?


THANKS, YOUR HELP IS MUCH APPRECIATED.




Homework Equations





The Attempt at a Solution

 
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welcome to pf!

hi mclj! welcome to pf! :wink:

i suppose they want you to calculate the deceleration? …

show us what you've tried, and where you're stuck, and then we'll know how to help! :smile:
 
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