Question

Rate of flow of water through a tube of radius 2mm is 8cm^3 and what is the rate of flow if radius of the tube is 1mm????

Answer 1

Answer : 2 cm³/s

$\rule{100}2$

Formula used

• We know that, the equation of continuity says : $\sf A_1 V_1 = A_2 V_2$

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It is given that,

• $\sf V_1 = 8\:cm^3/s$
• $\sf r_2 = 1 \:mm$
• $\sf r_1 = 2\:mm$

Now, substitute the given values in the equation. we get,

$\sf \pi {r_1}^2 \times v_1 = \pi {r_2}^2 \times v_2$

$\sf\implies v_2 = \dfrac{(r_1)^2}{(r_2)^2} \times v_1$

$\sf \implies v_2 = (\dfrac{1}{2})^2 \times 8$

$\sf\implies v_2 = \dfrac{1}{4} \times 8$

$\sf\therefore v_2 = 2 \:cm^3/s$

Ans :

The rate of flow is 2 cm³/s .

$\rule{200}2$