the linear speed of the seconds hand of a wall clock is 1.05cm/sec what will be the acceleration of the second hand

Question

 acceleration

 

Answer 1

The hand moves around the clock at 1.05 cm/sec.  You know that it will complete one circle around the clock in one minute.  So during that time it will travel 1.05 cm/sec x 60 sec = 63 cm. 

 

That tells us that the circumference of the circle that the hand travels in is 63 cm.  Since C = 2πr, we can use that to figure out the radius of the circle:  r = C / 2π = 63/2π = 10.03 cm.

 

The centripetal acceleration of the hand is v² / r, which in this case is (1.05 cm/sec)² / 10.03 cm = 0.11 cm / sec²