Projectile motion of a fired cannon ball

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A cannonball fired at a 36.9° angle towards a building 400 m away will hit in 5.0 seconds, confirmed by calculations using the horizontal component of velocity. When fired horizontally from a 150 m high cliff, the time to hit the building needs to be calculated differently. The horizontal velocity component is crucial for determining the impact time in this scenario. The initial velocity (V0) is stated as 100 m/s, which applies to the first question. The discussion emphasizes the importance of understanding projectile motion principles for accurate timing predictions.
KEVIN Phlem
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1. A cannonball is fired toward a vertical building 400 m away
with an initial velocity of at 36.9° above the horizontal.
The ball will hit the building in
A. 4.0 s. B. 5.0 s.
C. less than 4.0 s. D. more than 5.0 s.

2. If the cannonball in the previous question is fired horizontally
from a 150-m-high cliff, but still 400 m from the building, then
the ball will hit the building in
A. 4.0 s. B. 5.0 s.
C. less than 4.0 s. D. more than 5.0 sI used x =(Vo * Cos 36.9)t and got 5.0 s, which is correct, but i don't know how to solve for #2
 
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KEVIN Phlem said:
1. A cannonball is fired toward a vertical building 400 m away
with an initial velocity of at 36.9° above the horizontal.
The ball will hit the building in
A. 4.0 s. B. 5.0 s.
C. less than 4.0 s. D. more than 5.0 s.

2. If the cannonball in the previous question is fired horizontally
from a 150-m-high cliff, but still 400 m from the building, then
the ball will hit the building in
A. 4.0 s. B. 5.0 s.
C. less than 4.0 s. D. more than 5.0 sI used x =(Vo * Cos 36.9)t and got 5.0 s, which is correct, but i don't know how to solve for #2
What is the horizontal component of velocity in this case?

By the way: What is the value of V0 ?
 
100 m/s, sorry
 
KEVIN Phlem said:
100 m/s, sorry
That answers which question?
 
SammyS said:
That answers which question?
The first one.
 
KEVIN Phlem said:
The first one.
KEVIN Phlem said:
The first one.
In that case it must have answered both.

V0 is the horizontal component if it fired horizontally.
 
Thread 'Correct statement about size of wire to produce larger extension'

Thread 'Correct statement about size of wire to produce larger extension'

The answer is (B) but I don't really understand why. Based on formula of Young Modulus: $$x=\frac{FL}{AE}$$ The second wire made of the same material so it means they have same Young Modulus. Larger extension means larger value of ##x## so to get larger value of ##x## we can increase ##F## and ##L## and decrease ##A## I am not sure whether there is change in ##F## for first and second wire so I will just assume ##F## does not change. It leaves (B) and (C) as possible options so why is (C)...
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