The minute hand of a wall clock is 14 cm long. The displacement and distance covered by the tip of the minute hand from 9:00 a.m. to 9:30 a.m. are

Length of the minute hand of the clock, l = 14 cm.
We know,
Displacement is the shortest distance from the initial position to the final position.
When the minute hand is at 9.30 a.m, it is at a diametrically opposite position from 9.00 a.m. 
So displacement $\mathrm{s}=2\times 14$
$\Rightarrow \mathrm{s}=28 \mathrm{cm}$
Now,
The distance traveled by the minute hand is half of the circumference of the clock.
Distance $\mathrm{d}=2\mathrm{\pi r}/2$
$\Rightarrow \mathrm{d}=\mathrm{\pi r}$
$\Rightarrow \mathrm{d}=\frac{22}{7}\times 14$
$\Rightarrow \mathrm{d}=44 \mathrm{cm}$
The displacement and distance covered by the tip of the minute hand from 9:00 a.m. to 9:30 a.m. are 28 cm and 44 cm respectively.