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.
Let Karen's forward speed be considered as positive.
Therefore, before the headband is tossed backward, the speed of the headband is
V = 9 m/s
The headband is tossed backward relative to Karen at a speed of 20 m/s. Therefore the speed of the headband relative to Karen is
U = -20 m/s
The absolute speed of the headband, relative to a stationary observer is
V - U
= 9 + (-20)
= - 11 m/s
Answer:
The stationary observes the headband traveling (in the opposite direction to Karen) at a speed of 11 m/s backward.
Daguerreotype is defined as the
first practical photographic process which was introduced in Paris on January
7, 1839. To make the image permanent, Daguerre used salt solution. The result
of his introduced process is a finely defined image with surface which is
delicate. The major benefit of daguerreotype is if the images are correctly
preserved, the pictures could last forever. Aside from this, since it produces superior
quality of outline, it is thus suitable for portraitures.
Answer:
Explanation:
When the positively charged half shell is brought in contact with the electroscope, its needle deflects due to charge present on the shell.
When the negatively charged half shell is brought in contact with the positively charged shell , the positive and negative charge present on each shell neutralises each other .So both the shells lose their charges .The positive half shell also loses all its charges
When we separate the half shells , there will be no deflection in the electroscope because both the shell have already lost their charges and they have become neutral bodies . So they will not be able to produce any deflection in the electroscope.
