In an experiment with simple pendulum, a time measured was 40s for 20 vibrations when the length of the pendulum was taken as 100cm.
1.If the least count of the stop watch is .15 and that of metre scale is .1cm, Calculate the maximum permissible error in the measurement of gravitation 'g'?
2.If the actual value of 'g' at Delhi is 9.7915 m/s^2. Calculate the percentage error.

Show us how you have attempted to solve this problem and we'll help you if you get stuck. To start - do you know the formula to apply for a simple pendulum? If so, then try calculating 'g' from the data provided. Then recalculate 'g' using the min and max values for L and T in such a way that you get min and max possible values for 'g.' What do you get?