8. TERMS……………..
Length
Mass of bob
Oscillations
Equilibrium Position
Amplitude
Period
Frequency
9. LENGTH OF THE PENDULUM
The length of the
string from the point
of suspension to the
mass is called the
length of the
pendulum.
It is denoted by L
10. MASS OF THE BOB
A metal ball is used as
the bob of the
pendulum.
Its mass can be
measured by a common
balance
11. PERIODIC MOTION
The motion which
repeats itself after fixed
time intervals is called
periodic motion
The best example of periodic motion are the pendulum clocks.
12. TO AND FRO MOTION
The ball moves to and
fro. It rises to extreme
positions on both sides
and reverses its motion
Oscillations gradually
die down
13. MEAN POSITION OF THE PENDULUM
The central position of
the pendulum (the
starting position) is
called the mean position
of the pendulum.
It is labeled here as B.
14. EXTREME POSITIONS OF THE PENDULUM
A and C are the extreme positions of the pendulum.
15. OSCILLATION
To and fro motion of the
pendulum about a fixed
point
The motion of the mass
from its extreme position A
to C and back to A is called
an oscillation.
16. TIME TAKEN FOR ONE OSCILLATION
The time taken for one oscillation is very short and
therefore, difficult to measure accurately.
To find the time taken, we find the time taken for large
number say 20 oscillations. This time divided by 20
will give us time taken for one oscillation.
17. PERIOD (T)
The time taken for one complete oscillation.
It is sometimes also called its period and is denoted
by T.
T= time taken for a fixed no: of oscillatins ÷ No of
oscillations
T = t/n
n = no of oscillations
18. Amplitude (a)
The maximum
displacement of the bob
from the equilibrium
position
Here amplitude is AB or
BC
Represented by ‘a’
19. Frequency (f )
No: of Oscillations in one second
Represented by ‘ f ’
Frequency , f = 1 ÷ period = 1 ÷ T
f = n ÷ t
