Answer:
N = 2000 drops approx with 1 cm diameter each
Explanation:
Let the diameter of one drop is 1 cm
so volume of one drop is given by

now we have


now in 1L of liquid let say N drops are there
so we have

now we have


so it will have approx 2000 drops in it with diameter 1 cm each drop
Place the magnet at one end of the piece of metal. The magnet must make as much contact with the metal as possible. Place light pressure on the magnet and rub the metal in one direction only. Magnetization will take some time to accomplish so continue rubbing until the iron or steel attracts other pieces of metal.
Answer:


Δd = 
Explanation:
As
, when the car is making full stop,
.
. Therefore,

Apply the same formula above, with
and
, and the car is starting from 0 speed, we have

As
. After
, the car would have traveled a distance of

Hence 
As
we can simplify 
After t time, the train would have traveled a distance of 
Therefore, Δd would be 