Question

A small sphere of mass 2 kg is attached to the end of a cord of length 2 m and rotated in a vertical circle about a fixed point O. Determine the tension in the cord at the uppermost point of the trajectory if the speed at this point is 8 m/s. Use g=9.8 m/s2. Report your answer as a positive number in newtons.

Answer 1

Answer:

tension in the string at the top position of the ball will be given as

T = 44.4 N

Explanation:

At the top position of the trajectory we have force equation given as

$T + mg = \frac{mv^2}{R}$

here we have

$T = \frac{mv^2}{R} - mg$

so we have

$T = \frac{2(8^2)}{2} - (2 \times 9.8)$

$T = 64 - 19.6$

$T = 44.4 N$

So tension in the string at the top position of the ball will be given as

T = 44.4 N