Question

........ is the measure of angle b/w minute hand and hour hand at 4 o'clock

• A. ${180}^{\circ }$
• B. ${90}^{\circ }$
• C. ${120}^{\circ }$
• D. ${150}^{\circ }$

Answer 1

The correct option is C ${120}^{\circ }$

As shown in image.

At 4'O clock, this is the position of minute &

hour hand in the clock.

In 12 hrs the hours hand

moves through ${360}^{\circ }$

$\therefore$ for 12 hrs $\to$ hour hand moves ${360}^{\circ }$

For 1 hrs $\to$ hour hand moves $\frac{{360}^{\circ }}{12}={30}^{\circ }$

For 4 hrs $\to$ hour hand moves = ${30}^{\circ }\times 4$

$={120}^{\circ }$

$\therefore$ Angle between minute & hours hand

at 4'O clock is ${120}^{\circ }$