Question

calculate the speed of tip of seconds hand of a watch of length 15 cm

Answer 1

here radius = 15 cm
then circ. = 94.2cm(here it is our dist.)= .942m
time taken to complete in round = 60s.

speed = dist./time
.942m/60
=0.0157m/s

Answer 2

v=2xpiexr/t. =2x22/7x1.5 60. 60 seconds because,it is as given tip of seconds hand =2x22/7x15/10/60 =11/70 =0.157=0.16cm/s