Solution :
Given :
Mass of the object attached to the spring, m = 2 kg
Velocity of the object as it moves, V = 5 m/s
Amplitude of the object as it swings, A = 2.5 m
We have to find the frequency of the object.
We known,

Therefore, 

f = 0.32 Hz
Therefore the frequency of the object is 0.32 hertz when the amplitude of the 2 kg mass is 2.5 m moving a speed of 5 m/s.
B. A sandbar is formed by water. A sand dune is formed by wind.
The answer is nodes because nodes stay in a fixed position and i just learnt about this!
Answer:
v = 5.24 m/s
Explanation:
Given that,
No of spokes of a Ferris wheel = 60
The diameter of a wheel, d = 100 m
Radius, r = 50 m
It makes one rotation every 60 seconds.
We need to find the speed of the passengers when the Ferris wheel is rotating at this rate. Let it is v. It can be calculated as follows :

or
v = 5.24 m/s
So, the speed of the passengers is 5.24 m/s. Hence, the correct option is (A).