Question

Chapter 05, Problem 46 Reviewing Interactive Solution 5.46 will help in solving this problem. A stone is ted to a string Clength - 0.619 m) and whirled in a cirde at the same constant speed in two different ways. First, the circie is horizontal and the string is nearly parallel to the ground. Next, the orde is vertical. In the vertical case the maximum tension in the string is 5.10% larger than the tension that exists when the circle is horizontal. Determine the speed of the stone. Number the tolerance-/-2% Units

Answer 1

when horizontal,

T = m a_c = m v^2 / R

T = m v^2 / 0.619

when at bottom: (it will have maximum tension at this location)

T' - m g = m a_c =m v^2 / r

T' = m g + m v^2 / r

T' = 1.051 T

m g + m v^2 / r = 105.1 m v^2 / r

9.8 = (v^2 / 0.619) (1.051 - 1)

v = 10.9 m/s