Question

The short and long hands of a clock are 4 cm and 6 cm long respectively. Find the sum of distances travelled by their tips in 48 hours

Answer 1

Short hand is the hour hand and it completes 1 revolution in 12 hours.
In 12 hours, distance = 2πr = 2*22/7*4
And, in 2 days or 48 hours, the distance covered = 2*4*22/7*4
= 704/7
= 100.57 cm
Long hand is the minute hand and it completes 1 revolution in 1 hour.
So, in 48 hours, it will take 48 revolutions.
= 2*22/7*6*48
= 12672/7
= 1810.285
Total distance covered by the two hands = 100.57 + 1810.285
= 1910.855 cm

Answer 2

ANSWER ---->

Short hand is the hour hand and it completes 1 revolution in 12 hours.

In 12 hours, distance = 2πr = 2*22/7*4

And, in 2 days or 48 hours, the distance covered = 2*4*22/7*4

= 704/7

= 100.57 cm

Long hand is the minute hand and it completes 1 revolution in 1 hour.

So, in 48 hours, it will take 48 revolutions.

= 2*22/7*6*48

= 12672/7

= 1810.285

Total distance covered by the two hands = 100.57 + 1810.285

= 1910.855 cm