Question

Deep water runs almost still. What does it explain?

• A. Surface energy
• B. Equation of continuity
• C. Magnus effect
• D. Bernoulli's Theorem

Answer 1

The correct option is B

Equation of continuity

Let water be flowing in a river of width b. Let d₁ and d₂ (d₁ < d₂) be the depth of the river at two different places and V₁ and V₂ be the velocity of water at those places respectively.

So according to equation of continuity, we have

A₁V₁ = A₂V₂

or b d₁V₁ = b d₂V₂

or d₁V₁ = d₂V₂

since d₁ < d_2, V₁ > V₂

that is, where depth is more, speed is less and vice versa. Hence, deep water runs slow.