Wall clock diameter 20 cm. Determine the movement speed of the end of the minute hand.

We express the speed of movement of the end of the minute hand of the clock by the formula:
V = 2Π * R / T, where R is the radius of the wall clock (R = 0.5D, where D = 20 cm = 0.2 m, R = 0.5 * 0.2 = 0.1 m), T – the period of rotation of the end of the minute hand (T = 60 min = 60 * 60 = 3600 s).
Let’s calculate the speed of movement of the end of the minute hand:
V = 2Π * R / T = 2 * 3.14 * 0.1 / 3600 = 1.74 * 10 ^ -4 m / s.
V = 3.49 * 10 ^ -4 * 1000/3600 = 4.83 * 10 ^ -5 km / h.
Answer: The speed of the end of the minute hand is 1.74 * 10 ^ -4 m / s or 4.83 * 10 ^ -5 km / h.