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A piston of a syringe pushes a liquid ...

A piston of a syringe pushes a liquid with a speed of 1 cm, / sec . The radii of the syring tube and the needle are R = 1 cm and r = `0.5` mm respectively . The velocity of the liquid coming out of the needle is

A

2 cm/sec

B

400 cm,/sec

C

10 cm/sec

D

None of these

Text Solution

Verified by Experts

According to the equation of continuity ,
Av = av.
`rArr v. = (A//a)v`
where ` A = pi R^(2) and a = pir^(2)`
` rArr v . (R/r)^(2) v = ((1 cm )/(0.05 cm))^(2) (1 cm//sec ) = 400 ` cm/sec
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