Question

A $2.0m$ diameter propeller is rotating at $2500rpm$.
Which of the following values best represents the tangential velocity of the tip of the propeller blade?

• A. $262m/s$
• B. $524m/s$
• C. $1,050m/s$
• D. $15,700m/s$
• E. $2500m/s$

Answer 1

Answer: (A)

$262m/s$

Given : $\nu =2500$ $rpm=\frac{2500}{60}=41.67$ $rps$

Radius of the propeller $r=\frac{d}{2}=\frac{2.0}{2}=1.0$ m

Angular velocity $w=2\pi \nu =2\pi \times 41.67=261.67$ rad/s

$\therefore$ Tangential velocity of tip of blade $v=rw=1.0\times 216.67\approx 262$ m/s