Q. If two particles of masses m1 and m2 are moving towards each other with velocities v1 and v2, what is the total momentum of the system before they collide?
A.
m1 * v1 + m2 * v2
B.
m1 * v1 - m2 * v2
C.
m1 * v1 + m2 * v2 + m1 * m2
D.
0
Solution
The total momentum of the system before the collision is the vector sum of the momenta of the two particles, which is m1 * v1 + m2 * v2.
Q. In a perfectly inelastic collision, what happens to the kinetic energy of the system?
A.
It is conserved
B.
It is lost
C.
It is doubled
D.
It is halved
Solution
In a perfectly inelastic collision, the two colliding objects stick together, and some kinetic energy is transformed into other forms of energy, resulting in a loss of kinetic energy.
Q. In a system of particles, if the total external torque is zero, what can be said about the angular momentum of the system?
A.
It is constant
B.
It is increasing
C.
It is decreasing
D.
It is zero
Solution
If the total external torque acting on a system of particles is zero, the angular momentum of the system remains constant according to the conservation of angular momentum.
Q. In a system of particles, if the total momentum before a collision is equal to the total momentum after the collision, what type of collision is this?
A.
Elastic collision
B.
Inelastic collision
C.
Perfectly inelastic collision
D.
Explosive collision
Solution
This describes an elastic collision, where both momentum and kinetic energy are conserved.
