Question

A piston of a syringe pushes a liquid with a speed of 2 cm/sec. The radius of the needle is 1/10 times that of the tube. The velocity of the liquid coming out of the needle is

• A. 100 cm/sec
• B. 20 cm/sec
• C. 200 cm/sec
• D. 5 cm/s

Answer 1

Answer: (C)

200 cm/sec

Answer 2

According to the equation of continuity,

Av = A′v′

⇒ v′ = (A/A′)v = v =10² v = 200 cm/sec