The length of the string of a simple pendulum is measured with a metre scale to be 90.0 cm.The radius of the bob plus thelength of the hook is calculated to be 2.13 cm using measurements with a slide callipers. What is the effective lengthof the pendulum? (The effective length is defined as the distance between the point of suspension and the centre of the bob.)

Answer

A, B, C

Explanation

As shown in the ure

Actual Effective length = (90.0+2.13) m But, in the measurement 90.0 xm the no. of significant digits is only 2.
So the addition must be done by considering only 2 significant digits of each point. So, effective length =90.0+2.1=92.1 cm`