The watch makes one revolution in 1 hour, find the path and move the end of the hand in 15 minutes.

The watch makes one revolution in 1 hour, find the path and move the end of the hand in 15 minutes. if the arrow length is 10 cm

Given:

l = 10 centimeters = 0.1 meter – the length of the watch hand;

t = 1 hour = 60 minutes = 3600 seconds – the time during which the hand makes a full revolution;

t2 = 15 minutes = 900 seconds.

It is required to determine S (meters) – the movement of the arrow in time t2.

Find the circumference of the clock:

L = 2 * pi * r = 2 * 3.14 * 0.1 = 0.628 meters.

Then the speed of movement of the arrow:

v = L / t = 0.628 / 3600 = 0.00017 m / s.

In time t2, the arrow must move:

S = v * t2 = 0.00017 * 900 = 0.15 meters.

Answer: In 15 minutes, the arrow will move 0.15 meters (15 centimeters).