Answer:
X= 0.5 m
Explanation:
Given that
K= 640 N/m
m=10 kg
v= 4 m/s
We know that
kinetic energy of the mass
KE=1/2 m v²
Potential energy
PE=1/2 k X²
Given that kinetic and potential energy are equal
1/2 k X² = 1/2 m v²
k X² = m v²
Now by putting the values
640 X² = 10 x 4²
X= 0.5 m
So at 0.5 m kinetic and potential energy will be equal.
Answer:

Explanation:
given,
speed of wind, = 14 m/s
frequency of horn,f_s = 1000 Hz
speed of sound,V = 344 m/s
frequency heard by the listener
using Doppler effect
f_L is the frequency of the sound heard by the listener
f_s is the frequency of sound emitted by the listener
V is the speed of sound
v_L is the speed of listener
v_s is the speed of source
now,
considering the frame of reference in which wind is at rest now, both listener and the source will be moving at 14 m/s
now on solving we will get

hence, the frequency heard by the listener is equal to 1000 Hz
It's really hard to make out the gibberish at the end, where the list of choices should be.
Here are the three equations for the relationships among the wavelength, frequency, and wave-speed, for ANY wave:
-- Speed = (wavelength) x (frequency)
-- Wavelength = (Speed) / (frequency)
-- Frequency = (Speed) / (wavelength)
Notice that you only have to remember any ONE of these. Then you can always get the other ones by multiplying or dividing both sides by the same quantity.
If you want to remember all of them, here are the short forms:
V = L · f
L = V / f
f = V / L
The correct answer is transmission<<<<<<