Question

What fraction of clockwise revolution does the hour hand of a clock turn through –


(a) From 4 to 11
(b) 2 to 6


Also, find the number of right angles.​

Answer 1

$\large\underline\purple{\bold{Solution :- }}$

☆ We know that

$\tt\implies \: \boxed{ \red{ \bf \: 12 \: hours \: = \: 1 \: revolution }} \\ \tt\implies \: \boxed{ \red{ \bf \: \: 1 \: hour \: = \dfrac{1}{12} \: revolution}} \\ \tt\implies \: \boxed{ \red{ \bf \:1 \: revolution = 4 \: right \: angle }}$

$\bf \:\large \red{AηsωeR : a}$

● When we go from 4 to 11

$\tt\implies \:We \: move \: 7 \: hours$

$\tt\implies \:i.e. \: \dfrac{7}{12} \: revolutions$

$\tt\implies \:\dfrac{7}{12} \times 4 \: right \: angles$

$\tt\implies \:\dfrac{7}{3} \: right \: angles$

$\bf \:\large \red{AηsωeR : b}$

● When we go from 2 to 6

$\tt\implies \:We \: move \: 4 \: hours$

$\tt\implies \:i.e. \: \dfrac{4}{12} \: revolutions$

$\tt\implies \:\dfrac{1}{3} \: revolutions$

$\tt\implies \:\dfrac{1}{3} \times 4 \: right \: angles$

$\tt\implies \:\dfrac{4}{ 3} \: right \: angles$