dear xperts answer soon,

1. wats the difference between CONSTANT VELOCITY and UNIFORM VELOCITY ??
2. the second's hand of a watch is 2 cm long, then the speed of the tip of this hand is how much ?

1-There is no difference between uniform velocity and constant velocity. A body has a uniform or constant velocity if it travels in a specified direction in a straight line and moves over equal distances in equal interval of time.

2-

The circular path of the tip of the watch is, d = 2 × × r = 2 × 3.14 × 2 = 12.56 cm

The time in which the tip covers one revolution, t = 60 s

So,

The speed of the tip is,v = 12.56/60 = 0.21 cm/s