Given :
A rope 6m long is fixed at one end, the other end is attached to a light string so that it is free to move.
The speed of waves on the rope is 18 m/s.
To Find :
The frequency of the second harmonic.
Solution :
We know, for second harmonic wave :
Wavelength = Length of rope

Now, we know frequency is given by :

Therefore, the frequency of the second harmonic is 3 s⁻¹.
OPTION D is the correct answer.
Refer to the attachment for complete calculation...
Answer:
0.37 m/s to the left
Explanation:
Momentum is conserved. Initial momentum = final momentum.
m₁ u₁ + m₂ u₂ = m₁ v₁ + m₂ v₂
Initially, both the fisherman/boat and the package are at rest.
0 = m₁ v₁ + m₂ v₂
Plugging in values and solving:
0 = (82 kg + 112 kg) v + (15 kg) (4.8 m/s)
v = -0.37 m/s
The boat's velocity is 0.37 m/s to the left.
Runner 2 sees Runner 1 passing him with a velocity of 17 m/s west.
No they don’t. All the pictures we see if the universe are computer generated. Well, most of them are. We don’t exactly know how the milky way looks. It’s just very good guess.