Is Momentum Conserved in a Two-Object Collision?

  • Thread starter Thread starter sweedeljoseph
  • Start date Start date
  • Tags Tags
    Collision
AI Thread Summary
The discussion revolves around a physics problem involving a two-object collision on a frictionless surface. Participants are tasked with calculating the momentum components and determining whether linear momentum and kinetic energy are conserved during the collision. One user expresses uncertainty about completing the calculations beyond the first part, specifically regarding kinetic energy. Another user suggests focusing on calculating the kinetic energy before the collision as a next step. The conversation highlights the need for clarity in applying the relevant physics equations to solve the problem.
sweedeljoseph

Homework Statement



Two objects of masses M1 = 1 kilogram and M2 = 4 kilograms are free to slide on a horizontal frictionless surface. The objects collide and the magnitudes and directions of the velocities of the two objects before and after the collision are shown on the diagram below. (sin 37\circ = 0.6, cos 37\circ = 0.8, tan37\circ = 0.75).

*PICTURE ISNT WORKING SO HERES THE LINK*
http://img359.imageshack.us/img359/1051/probfk9.jpg

a) Calculate the x and y components (px and py, respectively) of the momenta of the two objects before and after the collision.
b) Show, using the data from the previous question, that linear momentum is conserved in this collision.
c) Calculate the kinetic energy of the two-object system before and after the collision.
d) Is kinetic energy conserved in the collision?

Homework Equations


p=mv
m1*v1+m2*v2=m1'*v1'+m2'*v2'
ke=1/2mv2

The Attempt at a Solution


i don't have all the answers from the teacher. i know how to do part a. but that's it. i don't know what else I am supposed to do after that.

the answer to part a is:
http://img262.imageshack.us/img262/4028/charttw5.jpg
you just use the p=mv to solve for everything.

i don't know how to do the rest. i think youre supposed to use the other formula i gave but i don't know. i need a lot of help.

thank you!
sweedeljoseph
 
Last edited by a moderator:
Physics news on Phys.org
You simply need to do what the question says, can you calculate the kinetic energy of the system before the collision?
 

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Similar threads

Solving Elastic Collision of Two Balls: Theory & Solutions
Replies
15
Views
3K
Elastic Collision and Momentum of Ice Skaters
Replies
16
Views
3K
Inelastic collisions -- how is momentum conserved but not energy?
Replies
5
Views
3K
Collision (Task help for medicine entry exam)
Replies
9
Views
1K
Elastic head-on collision problem
Replies
8
Views
2K
Conservation of momentum - with understanding
Replies
2
Views
2K
How Do You Solve for Final Velocities in Elastic Collisions?
Replies
20
Views
2K
Ambiguous question on momentum and how it works...
Replies
13
Views
1K
Collision problem: Two hockey pucks collide and stick together....
Replies
4
Views
2K
How to make m1 the subject of the formula
Replies
1
Views
2K

Hot Threads

Recent Insights

Back
Top