Investigating the Oscillations of a Pendulum
To investigate the oscillations of a simple pendulum and find the
value of Â‘gÂ’, acceleration due to gravity, in the laboratory.
Retort stand with clamp
Piece of thread (â‰ˆ 110 cm) Stop watch
Two small wooden blocks metre
Hypothesis and Theory:-
In this experiment the set up below is arranged. This is a simple
pendulum system which is a simple harmonic motion. In the figure below
consider a small mass m attached to the end of a length l of wire. The
other end is attached to a fixed point P and the mass oscillates along
the arc. Suppose the mass during the motion at a point B at an
instant, such that OB = y (displacement) and the angle at that moment
is Î¸ to PO. The downward force by the mass is mg so towards O it will
be horizontal component, that is, mg sin Î¸. The tension T by the
thread is balanced by the vertical component of the force by the bob.
So the only force acting is mg sin Î¸. Since Force= mass Ã—
-mg sin Î¸ = ma,
The negative sign indicates that it the direction is towards O.