Question

80. A lkg ball is rotated in a vertical circle by
using a string of length 0.1 m. If the tension
in the string at the lowest point is 29.4N, its
angular velocity at that position is
1) 7 rads-1
2) 14 rads-1
3) 3.5 rads- 4 ) 25.6 rads-1
WISDOM SERIES for Sri Chaitanya​

Answer 1

Answer:

answer is 14 rad/s please mark as brainliest

Answer 2

Answer:

Angular velocity, $\omega=14\ rad/s$

Explanation:

It is given that,

Mass of the ball, m = 1 kg

Length of the string, l = 0.1 m

Tension in the string at the lowest point is 29.4 N

Tension in the spring is equal to the sum of weight of the ball plus the centripetal force acting on it as :

$T=mg+\dfrac{mv^2}{r}$

$29.4=1\times 9.8+\dfrac{1\times v^2}{0.1}$

v = 1.4 m/s

Let $\omega$ is the angular velocity of the ball at that position. It is given by :

$\omega=\dfrac{v}{r}$

$\omega=\dfrac{1.4\ m/s}{0.1\ m}$

$\omega=14\ rad/s$

So, the angular velocity of the ball at the lowest point is 14 radian per second.