Posted by aj on .
the pendulum of a grandfather clock is 1.3m long. Determine the length of the arc through which the pendulum moves if it moves through an angle of 15

trig 
Reiny,
circumference of the potential whole circle = 2π(1.3)
= 2.6π
so , by a simple ratio
arc/2.6π = 15/360
arc = 2.6π(15/360) = (13/120)π or appr .34 m
or 34 cm