Question

Where will the hour hand of a clock stop if it starts: (a) From 6 and turns through 1 right angle? (b) From 8 and turns through 2 right angles? (c) From 10 and turns through 3 right angles? (d) From 7 and turns through 2 straight angles?

Answer 1

We need to find where will the hour hand of a clock stop for the given set of questions

Consider clock to be 360° and the clock marks up to 12

360/12 = 30 degrees per hour

(a) From 6 and turns through 1 right angle?

6 o’ clock = 6 X 30 = 180 °

From 180, a turn of right angle

180+90/ 30= 270/30= 9

So the hour hand would be at 9

(b) If the hour hand of a clock starts from 8 and turns through 2 right angle

8 o’clock = 8* 30° = 240°

240+2*90= 240+180= 420°

420/30= 14

We know that as per 24-hour format 14:oo hours stands for 2 o’clock

So, the hour hand would be at 2 o’clock

(c) If the hour hand of a clock starts from 10 and turns through 3 right angle

10 o’clock = 10* 30° = 300°

300+ 3*90 = 570/30 = 19

We know that as per 24-hour format 19:oo hours stands for 7 o’clock

So, the hour hand would be at 7 o’clock

(d) If the hour hand of a clock starts from 7 and turns through 2 straight angles, then it will stop at 7

7 o’ clock = 7* 30 = 210 °

210+ 2 * 180 = 210+360 = 570/30= 19

We know that as per 24-hour format 19:oo hours stands for 7 o’clock

So, the hour hand would be at 7 o’clock