Answer:
The normal strain along an axis oriented 45° from the positive x axis in the clockwise direction is -ε₀/2
Explanation:
Given that

From equation of normal strain in x direction:

Substituting the values:

Answer:
Explanation:
Suppose initially the plane was horizontal and light was reflected back at some angle θ from the normal .
Now the reflecting surface is twisted so that is becomes inclined at angle alpha .
The reflected light will be deviated from its original direction by angle
2 x alpha .
Similarly when the reflecting surface is further twisted so that it becomes inclined at angle beta then again the reflected beam will deviated by angle
2 x beta
Hence angle between these two reflected beam
= 2 beta - 2 alpha
= 2 ( β - α )
So, angular separation between the rays reflected from the two surfaces
= 2 ( β - α ) .
Answer:
c. nine times as low.
Explanation:
Sound intensity is defined as the acoustic power transferred by a sound wave per unit of normal area to the direction of propagation:

Since the sound wave has a spherical wavefront of radius r, then the area is given by:

Here r is the distance from the source of the sound. Thus sound intensity decreases as:

law of electromagnetic induction hope this helps