Question

A hard drive disk rotates at 7200 rpm. The disk has a diameter of 5.1 in (13 cm). What is the speed of a point 6.0 cm from the center axle

Answer 1

Answer:

The speed will be "3.4×10⁴ m/s²".

Explanation:

The given values are:

Angular speed,

w = 7200 rpm

i.e.,

  = $7200 \times \frac{2 \pi}{60}$

  = $753.6 \ rad/s$

Speed from the center,

r = 6.0 cm

As we know,

⇒  Linear speed, $v=wr$

On putting the estimated values, we get

                               $=753.6\times 0.06$

                               $=45.216 \ m$

Now,

Acceleration on disk will be:

⇒  $a=\frac{v^2}{r}$

       $=34074 \ m/s^2$

       $=3.4\times 10^4 \ m/s^2$