Page 132 - Physics - XI

Observations
Constant frequency of the tuning fork = n = .... Hz

Table for calculation of resonant length and tension in the wire

Load Resonant length of the wire
including the Tension Mean 2 T
S. No. mass of the T = Mg Length Length l l l 2 l 2
hanger (N) increasing decreasing l 1 2 2 (cm ) (N cm )
–2
M (kg) l (cm) l (cm) (cm)
1
2
1.
2.
3.
4.
5.
6.

Y
Graph

1. Within the limits of the experimental error, the value of T/l is
2
found to be constant for all the observations.

2. Plot a graph between l and tension T, taking T along X-axis l 2 (cm 2 ) Scale used on:
2
X-axis, 1 cm = ... N
and l along Y-axis. The graph will be a straight line as shown in Y-axis, 1 cm = ... cm 2
2
Fig. 9.1.
Tension T (N) X
2
Result Fig. 9.1: Variation of l with T
1. The graph plotted between l and T is a straight line as shown in the Fig. 9.1.
2
2. We fi nd that within the experimental error, the value of T/l is constant for all the observations.
2
So, T ∝ l for a constant frequency n.
2
Precautions

Same as experiment 8.

Sources of Error

Same as experiment 8.

VIVA VOCE

Q1. What is a sonometer?
Ans. It is an instrument which is used to study the vibrations produced by vibrating strings. It is also
called monochord.

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