Using that velocity, and the information from above, compare the total momentum just before the collision with the total momentum after the collision. (again let the masses of the balls be m) , it is a lab question , i was just wondering what formula to use for the momentum
To compare the total momentum just before and after the collision, you can use the principle of conservation of momentum. According to this principle, the total momentum of an isolated system remains constant if there are no external forces acting on it.
The formula for momentum is given by:
P = m * v
where P is the momentum, m is the mass of the object, and v is the velocity of the object.
In your case, you mentioned that the masses of the balls are denoted as 'm'. Let's assume the velocities of the balls just before the collision are v1 and v2, and the velocities just after the collision are v1' and v2'.
The total momentum just before the collision (P_initial) is the sum of the individual momenta of the balls:
P_initial = (m * v1) + (m * v2)
The total momentum after the collision (P_final) can be calculated in the same way:
P_final = (m * v1') + (m * v2')
To compare the total momentum just before and after the collision, you can calculate both P_initial and P_final using the individual momenta of the balls and compare the values.
If P_initial is equal to P_final, it means that the total momentum of the system is conserved, indicating an elastic collision. If P_initial is not equal to P_final, then the momentum is not conserved, indicating an inelastic collision.
Remember to use consistent units for mass and velocity when using the momentum formula.