Question

A 0.550-kilogram ball attached to a string swings along a circularpath of radius 0.250 meter, as shown. The instantaneous linearspeed of the ball is 2.15 meters per second. What is the tension inthe string?(a) 11.5 N(b) 10.8 N(c) 7.19 N(d) 5.40 N

Answer 1

Given data:

The mass of the attached ball to the string is,

$m=0.55\text{ kg}$

The radius of the circular path is,

$r=0.25\text{ m}$

The initial velocity of the ball is,

$u=2.15ms^{-1}$

The tension in the string in terms of velocity, mass and radius of the path is,

$T=\frac{mu^2}{r}$

Substituting the known values,

$\begin{gathered} T=\frac{0.55\times2.15^2}{0.25} \\ T=10.8\text{ N} \end{gathered}$

Thus, the tension in the string is 10.8 N.

Hence, the option b is the correct answer.