Calculate Swing Length of Ballistic Pendulum | 25-gm Bullet at 300m/sec

AI Thread Summary
A 25-gm bullet traveling at 300 m/sec strikes a ballistic pendulum block weighing 98N, which is suspended by a 1 m cord. The bullet embeds itself in the block, prompting a discussion on using conservation of momentum to determine the initial velocity and conservation of energy to find the height of the swing. Participants clarify that the block moves in a circular arc with a radius of 1 m. The conversation also touches on calculating the arc length based on the angle of swing. The thread emphasizes the importance of understanding the physics principles involved in the ballistic pendulum scenario.
acissej_o3
Messages
3
Reaction score
0
a 25-gm bullet traveling with a speed of 300m/sec strikes the block of a ballistic pendulum. the block weighs 98N and is supported by a light cord 1 m long. calculate the length of the arc through which the pendulum swings.
 
Physics news on Phys.org
Welcome to PF!

acissej_o3 said:
a 25-gm bullet traveling with a speed of 300m/sec strikes the block of a ballistic pendulum. the block weighs 98N and is supported by a light cord 1 m long. calculate the length of the arc through which the pendulum swings.

Hi acissej_o3! Welcome to PF! :smile:

Hint: the bullet will be embedded in the block, so they will move together.

Use conservation of momentum to find the initial velocity, and then use conservation of energy to find the height! :smile:
 


tiny-tim said:
Hi acissej_o3! Welcome to PF! :smile:

Hint: the bullet will be embedded in the block, so they will move together.

Use conservation of momentum to find the initial velocity, and then use conservation of energy to find the height! :smile:

i have computed for the height. i don't know how to compute for the arc... tnx for replying:)
 
acissej_o3 said:
i have computed for the height. i don't know how to compute for the arc...

easy-peasy! :smile:

the block moves on a circle of radius 1m …

so the cos of the angle is … ? :wink:
 
tiny-tim said:
easy-peasy! :smile:

the block moves on a circle of radius 1m …

so the cos of the angle is … ? :wink:

y is it zero?
 
Last edited:

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 'Collision of a bullet on a rod-string system: query'

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
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

Linear momentum problem (ballistic pendulum)
Replies
2
Views
4K
Conservation of Energy Problem -- bullet fired into a ballistic pendulum
Replies
7
Views
6K
Ballistic Pendulum initial velocity of bullet
Replies
2
Views
3K
Calculate the New Velocity and the Velocity of a Pendulum Mass
Replies
1
Views
1K
How Is Momentum Conserved in a Bullet and Ballistic Pendulum Collision?
Replies
3
Views
2K
Ballistic Pendulum: Find the Bullet's Speed
Replies
2
Views
2K
Ballistic Pendulum kinetic energy
Replies
8
Views
18K
Ballistic Pendulum Problem: Determining Speeds of Bullet and Block
Replies
3
Views
9K
Velocity of bullet before hitting a pendulum
Replies
11
Views
3K
Momentum conservation (ballistic pendulum)
Replies
2
Views
1K

Hot Threads

Recent Insights

Back
Top