Question

A particle describes a horizontal circle in a conical funnel whose inner surface is smooth with speed of 0.5 m/s. What is the height of the plane of circle from vertex of the funnel?

• A. 0.25 cm
• B. 2 cm
• C. 4 cm
• D. 2.5 cm

Answer 1

Answer: (D)

2.5 cm

Answer 2

Nsinq = mg

Ncosq = mv²/r

̃ tanq = rg/v²

̃ $\frac{r}{h} = \frac{rg}{v^{2}}$

̃ h = $\frac{v^{2}}{g}$= 2.5 cm