The only condition under which a concave mirror forms a virtual and upright image on the principal axis is when there is a concave mirror with the object in front of the focal point. This is the only positioning available for the said image to be formed.
It would be c repeated processes-that are used in a variety of ways
Answer:
Oblique surface
Explanation:
Surfaces or lines situated at an angle in relation to all the main projection planes are oblique. An oblique surface never appears in any of the main perspectives as a line or true size area. It's Tipped to all main projection planes. doesn't quite appear on the edge of every standard view. doesn't quite show up in any view in true size.it has always been foreshortened.
Answer: Electron affinity increases on moving across a period.
Explanation:
When an electron is added to a neutral atom to convert it into a negative ion, the tendency is known as electron affinity.
Smaller is the size of an atom more readily an electron will be gained by it because of strong force of attraction exerted by its nucleus towards the electron.
As moving from left to right in a period, more and more electrons get added up in the same shell and the attraction between the last electron and nucleus increases, which results in the shrinkage of size of an atom.
Also, size of atoms decreases from left to right in a periodic table, thus tendency to gain electrons will also increase on moving from left to right.
So, on moving across a period, there will be an increase in electron affinity.
Answer:
20 Hz
15.8 times
Explanation:
A
Although the range of frequency for any human's ear is usually said to be between 20 Hz and 20 kHz. And since the question asked for the least intense frequency, that has to be 20 Hz. Essentially the frequency most people perceive the least intense sound is 20 Hz.
B
A 100-Hz sound must be 10^1.2 times or 15.8 times more intense compared to a 1000-Hz sound to be perceived as equal to 60 phons of loudness