Projectile motion of a fired cannon ball

AI Thread Summary
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
Messages
4
Reaction score
0
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
 
Physics news on Phys.org
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 'Errors and significant figures'

I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
View full post »
Thread 'A cylinder connected to a hanging mass'

Thread 'A cylinder connected to a hanging mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
View full post »

Similar threads

Projectile Motion with Pulley System
Replies
3
Views
2K
I need opinions on a Projectile Motion problem that I made up
Replies
11
Views
2K
Projectile motion of a cannon ball versus time
Replies
15
Views
2K
Find the Height of a Building by dropping a ball from the top
Replies
7
Views
3K
Projectile Motion Problem: Kicking a soccer ball over a fence
Replies
11
Views
2K
How Do You Solve a Projectile Motion Problem?
Replies
3
Views
4K
Projectile Motion -- Help please understanding these basic problems
Replies
4
Views
1K
Railway/Cannon - Conservation of Momentum HW Problem
Replies
9
Views
2K
Projectile Motion of a Cannonball: Calculating Velocity, Height, Time, and Range
Replies
5
Views
2K
Projectile Motion Experimental Error
Replies
1
Views
2K

Hot Threads

Recent Insights

Back
Top