Question

I want to know when to use Conservation of momentum

Answer 1

Conservation of momentum holds for a system when there are no external forces on the system. Since momentum is a vector, we need to check the net force in each direction, and if the net force is zero then the momentum for that direction is conserved.

Answer 2

" Since momentum is a vector, we need to check the net force in each direction, and if the net force is zero then the momentum for that direction is conserved"


that's quite misleading what you are saying :P

Just remember No net EXTERNAL force, then Momentum of the system is conserved!

Answer 3

Ok so basically ignore my second sentence lol.

Answer 4

:D.. yup!

Answer 5

but i cant figure out when to apply it still .-. and HOW to apply it

Answer 6

i ll give u a problem
A gun of mass 1kg, shoots a bullet of mass 1 gram, forward with a muzzle velocity of 300m/s. Calculate

a) Net momentum of the gun and the bullet system before the shot was fired
b) is there any External force on the gun and bullet before or after it was fired?
c) Net momentum of the gun and the bullet system AFTER the shot was fired
d) momentum of the bullet
e) momentum of the gun
f) velocity of the gun (recoil)

Answer 7

A)Initial=0?
B)No (mg is an internal force right?)
C)M(-v)+mv i suppose..
D) mv
E) M(-v)
F)
Mv=mv
I AM CONFUSED :/
what will be the V of gun ? after it is shot..will it be same but -ve of bullet?

Answer 8

if there is no net external force.. then the final momentum of the system should be exactly same as the initial momentum!

Answer 9

u didn't answer my question e.e

Answer 10

Final should be 0 too? o.O and speed of gun please

Answer 11

u tell..

if the final momentum must be zero.. what should be the momentum of the gun
give me numerical answers to all of the above plz!

Answer 12

A gun of mass 1kg, shoots a bullet of mass 1 gram, forward with a muzzle velocity of 300m/s. Calculate

a) Net momentum of the gun and the bullet system before the shot was fired
b) is there any External force on the gun and bullet before or after it was fired?
c) Net momentum of the gun and the bullet system AFTER the shot was fired
d) momentum of the bullet
e) momentum of the gun
f) velocity of the gun (recoil)

A) 0
B)No
C)\(1(-300) + (\frac{1}{1000} \times 300)\)
D) \(\frac{1}{1000} \times 300\)
E)\(1(-300)\)
F)\(-300 m/s\)
Out of which C E and F are wrong coz idk..

Answer 13

@Mashy

Answer 14

I ALREADY TOLD U FINAL MOMENTUM MUST BE ZERO!!!!!!

Answer 15

yes but how is that possible :|

Answer 16

u will convert g to kg :o

Answer 17

A gun of mass 1kg, shoots a bullet of mass 1 gram, forward with a muzzle velocity of 300m/s. Calculate

a) Net momentum of the gun and the bullet system before the shot was fired
b) is there any External force on the gun and bullet before or after it was fired?
c) Net momentum of the gun and the bullet system AFTER the shot was fired
d) momentum of the bullet
e) momentum of the gun
f) velocity of the gun (recoil)

A) 0
B) No
C) \(\large P_f=-M_{gun}V+m_{bull}v\)
=>\(-1.V+\frac{1}{1000} \times 300\)
D)\((\frac{1}{1000} \times 300)\)
e) 1.v'=v'
f) \(\frac{1}{1000} \times 300\)
?