What Is the Ratio of Distances Each Block Travels After a Firecracker Explosion?

AI Thread Summary
After a firecracker explosion, a wooden block split into two pieces—one three times the mass of the other—travels different distances. The lighter block moves with a velocity that is one-third that of the heavier block. Consequently, the ratio of the distances each block travels after the explosion is 1:3. This conclusion is based on the principle of conservation of momentum, where the lighter block covers more distance due to its lower mass. Understanding this ratio helps in solving similar physics problems involving explosions and motion.
pb23me
Messages
204
Reaction score
0

Homework Statement


A wooden block is cut into two pieces, one with three times the mass of the other. A depression is made in both faces of the cut, so that a firecracker can be placed in it with the block reassembled. The reassembled block is set on a rough-surfaced table, and the fuse is lit. When the firecracker explodes, the two blocks separate and slide apart. What is the ration of distances each block travels?




Homework Equations


4mv=3mv-mv
4mv=0 so 3v=v


The Attempt at a Solution

I see that one velocity is one third of the other but I am not sure what answer to give as to how far each block travels?
 
Physics news on Phys.org
You don't need to know how far, just the ratio of their distances.

Hint: If you run twice as fast as I do (and we start at the same time and go in opposite directions), what's the ratio of our distances from the starting point at any time? (Make up some numbers and see how it works.)
 
ok it seems like it would just be 1/3
 
That's it.
 

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

Velocity and distance ratio problem
Replies
1
Views
7K
Why is momentum conservation always true in a collision?
Replies
4
Views
2K
Calculating Distance Traveled by Cart with Sliding Block
Replies
9
Views
3K
Confusion with "explosive" part, Conservation of Momentum
Replies
6
Views
2K
Bullet passes through block - conservation of momentum
Replies
5
Views
3K
Conservation of energy and momentum Problem
Replies
1
Views
1K
Spring Compression (x-x0) = .00579 m
Replies
1
Views
2K
Velocities and momentum after explosions
Replies
1
Views
3K
Explosion and conservation of momentum problem
Replies
5
Views
2K
How do I figure out the final position of the block?
Replies
4
Views
3K

Hot Threads

Recent Insights

Back
Top