All Questions
Tagged with momentum homework-and-exercises
580
questions
4
votes
2
answers
755
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After how many bounces will a ball's mechanical energy equal zero?
This was a question I asked myself for fun. It turned out to be more difficult than I initially imagined.
The Problem: Let's say a ball is dropped from h0. Air friction is negligible. The collisions ...
- 119
-1
votes
2
answers
65
views
Total momentum of a fluid in a pipe [closed]
Suppose we have a cylindrical pipe let's say length L = 10
m and radius R = 1 m through which water is flowing. The velocity distribution is given by Poiseuille's Law: $v(r)=\frac{\Delta P}{4L\eta}\...
0
votes
1
answer
63
views
Confusion in conservation of momentum [closed]
Two masses $m_1$ and $m_2$ are attached to the two ends of a rope that is sent through a pulley. Then a mass $M$ is dropped onto the mass $m_1$ from a $h$ height. So when the law of conservation of ...
- 145
0
votes
2
answers
68
views
Ball colliding with inclined stationary plane
A particle with mass m1 is dropped from a height onto an incline plane creating the angle $\alpha$ with the ground (the slope is frictionless). The coefficient of restitution is e. Find the angle $\...
1
vote
1
answer
29
views
Im confused on how conservation of momentum works mathematically for a problem involving a skater throwing two weights from rest [closed]
Here's the question.
A 40-kg skateboarder on a 3-kg board is training with two 5-kg weights. Beginning from rest, she throws the weights horizontally, one at a time from her board. The speed of each ...
- 13
0
votes
0
answers
25
views
How to show that $G_p=SO(D-1)$?
Let $G=SO(D-1,1)^{\uparrow}$ be the connected Lorentz group. Let $p$ be a timelike momentum with $p_0>0$. I want to show that $G_p=SO(D-1)$, the little group of $p=(M,0,\ldots,0)$ where $M>0$....
- 374
6
votes
4
answers
374
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Very interesting case, where energy is not conserved?
This is not a homework problem. I have a bigger, more conceptual doubt behind it.
Applying linear momentum conservation: We get velocity of disc is v (towards right)
Now, friction will also apply a ...
- 278
2
votes
1
answer
179
views
Do we know that energy of a system is conserved if no external forces do work on it?
This question is from K&K's intro book on mechanics. The larger block with the quarter circle missing has mass $M$ and the smaller block has mass $m$. The goal is to find the speed $v$ of the ...
1
vote
1
answer
207
views
Why is energy conservation not valid here? [closed]
I was solving this question and I faced a problem :
See the problem is I know the conventional way of impulse momentum and energy conservation to solve this question but ,
I do not know why applying ...
0
votes
4
answers
64
views
Percentage change in K.E for a given change in momentum
I couldn't get through this 'easy question' that was in my morning exam, it goes
Q. If linear momentum of body is increased by 50%, then K.E of that body increases by....%
**My solution **
K.E = $E=\...
- 367
1
vote
1
answer
42
views
Elastic collision between 2 particles in 2D [closed]
A particle with mass $m_1=m$ moves along the x-axis at a velocity of $v_0$ and collides with another particle $m_2=4m$. As a result of the collision $m_1$ travels upwards at an angle of $90 ^\circ$. (...
- 111
0
votes
1
answer
21
views
Two bodies that collided inelastically and rebounded [closed]
I can't find the solution to this problem.
0
votes
1
answer
40
views
Ball collisions
When two balls collide directly, the impulse of the collision acts along the line of centers, so the momentum along this direction is not conserved. Therefore, I can only use the conservation of ...
- 75
1
vote
1
answer
68
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Conservation of Kinetic energy in splitting
If a stationary mass $M$ explodes into 2 masses $m_1$ and $m_2$ with velocity $v_1 $and $v_2$ respectively releasing no energy in any other form like sound and heat.
Then I've read that-
intial k.E = ...
- 367
-4
votes
3
answers
80
views
How do you prove the formula for momentum? [closed]
I am just an absolute beginner to physics. I've seen a proof of the formula for momentum using Newton's second law of motion, but to prove Newton's second law of motion you have to use the formula for ...
