Answer
given,
Length of the string, L = 2 m
speed of the wave , v = 50 m/s
string is stretched between two string
For the waves the nodes must be between the strings
the wavelength is given by

where n is the number of antinodes; n = 1,2,3,...
the frequency expression is given by

now, wavelength calculation
n = 1

λ₁ = 4 m
n = 2

λ₂ = 2 m
n =3

λ₃ = 1.333 m
now, frequency calculation
n = 1


f₁ = 12.5 Hz
n = 2


f₂= 25 Hz
n = 3


f₃ = 37.5 Hz
The answer would be 0.40m. you are finding how far the distance is between 10 and 50
1) sound velocity reported by you : 292.39 m /s
2) time to travel 1620m at that velocity: t = d / v = 1620 m / 292.39 m/s = 5.54 s, since the moment the sound wave started.
3) You might wanted to tell the time since you watched the lightning.
Then you can calculate the time since the lighting was generated,1620 m away from you, until you saw it, using the speed of light:
speed of light = 3*10^8 m/s => t = 1620 m / (3*10^8m/s) =0.0000054 s
Then, this time is completely neglectible, and yet the answer is 5.54 s, as calculated in the step 2.
Answer:
Option B
0.3 m/s2 South
Explanation:
Acceleration,
where v and u are final and initial velocities respectively, t is the time taken
Substituting 14.1 m/s for v, 17.7 m/s for u and 12 s for t then

Since this is negative acceleration, it's direction is opposite hence 0.3 m/s2 South