Answer:
Acceleration due to gravity will be 
Explanation:
We have given length of pendulum l = 55 cm = 0.55 m
It is given that pendulum completed 100 swings in 145 sec
So time taken by pendulum for 1 swing 
We have to find the acceleration due to gravity at that point
We know that time period of pendulum;um is given by

So 

Squaring both side


So acceleration due to gravity will be 
To solve this problem we will apply the concepts related to wave velocity as a function of the tension and linear mass density. This is

Here
v = Wave speed
T = Tension
= Linear mass density
From this proportion we can realize that the speed of the wave is directly proportional to the square of the tension

Therefore, if there is an increase in tension of 4, the velocity will increase the square root of that proportion
The factor that the wave speed change is 2.
Momentum = mass*velocity(or speed)
241.5 kg*m/s = 115 kg * v
v = 241.5 kg*m/s / 115 kg = 2.10 m/s
Answer:
The length is 
Explanation:
From the question we are told that
The frequencies of the two successive harmonics are
, 
The speed of sound in the air is 
Generally the frequency of a given harmonic is mathematically represented as

Here n defines the position of the harmonics
Now since the position of both harmonic is not know but we know that they successive then we can represented them mathematically as

and

So

=> 
=> 