Fast Communication, can be used for good and can be used for bad hackers.
Answer:
5.4 ms⁻¹
Explanation:
Here we have to use conservation of energy. Initially when the stick is held vertical, its center of mass is at some height above the ground, hence the stick has some gravitational potential energy. As the stick is allowed to fall, its rotates about one. gravitational potential energy of the stick gets converted into rotational kinetic energy.
= length of the meter stick = 1 m
= mass of the meter stick
= angular speed of the meter stick as it hits the floor
= speed of the other end of the stick
we know that, linear speed and angular speed are related as

= height of center of mass of meter stick above the floor = 
= Moment of inertia of the stick about one end
For a stick, momentof inertia about one end has the formula as

Using conservation of energy
Rotational kinetic energy of the stick = gravitational potential energy

Answer:
Option B) This minimizes the harmful side effects of the radiations
Explanation:
Half-life is the time taken for the decay of an radio-active atom in which it disintegrates such that it becomes half of its value at the beginning.... The nuclei should be in active mode for a longer duration sufficient for the treatment of the condition but these nuclei should have a sufficient shorter half life so that they don't get enough time to cause any damage to the health of the person other than treating the cause.
A shorter half life gives the assurance that the radiation after the treatment will leave the body without getting accumulated and cause harm to the body cells and other organs.