Kinetic energy, KE, is modeled by the formula

, where m is the mass in kg and v is the velocity in m/s.
In this scenario, mass and one-half are constant but the velocity changes.
You can see that by squaring twice the velocity, that is equal to four times the original KE. Therefore, the answer is 4k.
The ice and how the blades are made
Decrease the amount of force applied
Given Information:
Wavelength = λ = 39.1 cm = 0.391 m
speed of sound = v = 344 m/s
linear density = μ = 0.660 g/m = 0.00066 kg/m
tension = T = 160 N
Required Information:
Length of the vibrating string = L = ?
Answer:
Length of the vibrating string = 0.28 m
Explanation:
The frequency of beautiful note is
f = v/λ
f = 344/0.391
f = 879.79 Hz
As we know, the speed of the wave is
v = √T/μ
v = √160/0.00066
v = 492.36 m/s
The wavelength of the string is
λ = v/f
λ = 492.36/879.79
λ = 0.5596 m
and finally the length of the vibrating string is
λ = 2L
L = λ/2
L = 0.5596/2
L = 0.28 m
Therefore, the vibrating section of the violin string is 0.28 m long.