Question

Take a spring of medium stiffness, about 20 cm in length. Fix the upper end of the spring to a rigid support. On the lower end attach a scale pan of known mass so that the system hangs vertically. Pull the pan 1-2 cm downwards and release. The pan will oscillate up and down. Measure the time of 20 oscillations with the help of a stop watch and calculate the time period of oscillation of pan. Now place a middle size pebble on the pan, set it in oscillations and determine the time period of oscillation again. Calculate the mass of the pebble using the data obtained from your observations.

Answer 1

Here M is Mass of the pan and pebble, so mass of pan m needs to be subtracted from M for the final mass.

Answer 2

When you take a string of a medium stiffness of about 20cm in length fis the ipper end of the string to a rigid support .then on the lower end attach a scale pan of a known mass so that the system hangs vertically .

Pull the pan 12m below and release it

The pan will oscilate up and down then measure the time of 20 oscilations