30 minutes I am not sure about that
It’s going to be both answer A and B but if you can only answer one then it’s going to be B
Answer:
1. Elastic collision
2. Inelastic collision
Explanation:
Elastic collision: collision is said to be elastic if total kinetic energy is not conserved and if there is a rebound after collision
the collision is described by the equation bellow

Inelastic collision: this type of collision occurs when the total kinetic energy of a body is conserved or when the bodies sticks together and move with a common velocity
the collision is described by the equation bellow

Answer:
1.98s
Explanation:
The time taken to hit the ground is given by
h=ut+ 1/2 at^2
but u =0
so we have
h=1/2at^2
making t the subject
t=√2h/g
√2×19.6/10
1.98s
False. First Law of Newton states that object tends to be at rest until an external force is applied and vice-versa.