Question

Angle between the minutes hand of a clock and hour hand when the time is 7 : 20 am is

• A. ${80}^{\circ }$
• B. ${100}^{\circ }$
• C. ${120}^{\circ }$
• D. ${140}^{\circ }$

Answer 1

The correct option is B ${100}^{\circ }$

We know that the hour hand completes one radtion in 12 h, while the minute hand completes one rotation in 60 min.

Therefore, the angle traced by the hour hand in 12 h is 360${}^o$

Angle traced by the hour hand in 7 h 20 min i.e. $\frac{22}{3}h=(\frac{360}{12}\times \frac{22}{3})={220}^o$

Also, angle traced by the minute hand in 60 min = 360${}^o$

Angle traced by the minute hand in 20 min $=(\frac{360}{60}\times 20)={120}^o$

Hence , required angle between the wo hands $={220}^o-{120}^o={100}^o$

Option B is the correct answer.