A light year is a unit of distance. It is a distance that light can travel in a years time which is six trillion miles. It is used to measure the distances in space. To take one example, the distance to the next nearest big galaxy, the Andromeda Galaxy, from earth is 21,000,000,000,000,000,000 km.
Do you understand it? <span />
Answer:
Pressure applied to the needle is 7528 Pa
Explanation:
As we know by poiseuille's law of flow of liquid through a cylindrical pipe
the rate of flow through the pipe is given as

now we know that

radius = 0.2 mm
Length = 6.32 cm

now we have



now we have


143m/s if you just perhaps by what you know you'll figure it out