Question

Find the number of right angles turned through by the hour hand of a clock when it goes from $3$ to $6$.

Answer 1

Find the number of right angles when hour hand of a clock goes from $3$ to $6$.

So, the hour hand of a clock moves from $3$ to $6$ shown in figure

From $3$ to $6$, hour hand has travelled $3$ hours.

There are total $12$ hours written on a clock and by covering $12$ hours, an hour hand has covered $360°$ (a circle)

$\Rightarrow$ Angle travelled by hour hand in $1$hour $=\frac{360}{12}=30°$

So, for travelling $3$ hours , the hour hand will cover,

$\Rightarrow$ $\frac{360}{12}\times 3=90°$

$=1$ right angle

Hence, the hour hand goes through $1$ right angle starting from $3$ to $6$.