Answer:
just-noticeable difference
Explanation:
Using principles of psychology and physics, a branch of experimental psychology called psychophysics has been created. This field is focused on the sensation, the sense and the perception of stimuli. Within this branch it has been called just-noticeable difference to the amount that must be changed of some stimulus so that this difference is noticeable, that is to say, the threshold at which the change is perceived.
Answer:
1.1 sec
Explanation:
m = mass of the box = 8 kg
k = spring constant of the spring = 69 N/m
v = initial speed of the box = 1.5 m/s
t = time period of oscillation of box in contact with the spring
Time period is given as

Inserting the values

t = 1.1 sec
We know that the measure of an incident ray is: α 1 = 40°.
The index of refraction:
- for the air : n 1 = 1.00,
- for the water: n 2 = 1.33
Snell`s Law of Refraction :
n 1 · sin α 1 = n 2 · sin α 2
sin α 2 = n 1 · sin α 1 / n 2 =
= 1.00 · sin 40° / 1.33 = 0.64278 / 1.33 = 0.4833
α 2 = sin ^(-1) 0.4833
α 2 = 28.9 °
Answer: The angle relative to the water`s surface of the rays when beneath the surface is 28.9°.
Answer:
f3 = 102 Hz
Explanation:
To find the frequency of the sound produced by the pipe you use the following formula:

n: number of the harmonic = 3
vs: speed of sound = 340 m/s
L: length of the pipe = 2.5 m
You replace the values of n, L and vs in order to calculate the frequency:

hence, the frequency of the third overtone is 102 Hz
The formula for potential energy is PE=mgh
It can have that high of a potential energy if it's relative height what super high.