Answer:
.C. Refraction of light passing through the lens.
Explanation:
The convergence or divergence of the rays of light is only due to refraction of light. When a ray of light is made to pass through a lens, it bend's from it's original path. This bending of light from its original path is called Refraction. Whereas in Reflection the ray of light is reflected back into the same medium.
Hence the correct option is C. Refraction of light passing through the lens.
<span>They are poor insulators because the electrons in the atom are tightly bound and unable to move between other atoms.
</span>
The solutions would be :
1. C
2. B
3. A
4. C
5. D.
Answer:

Explanation:
Given


Required
Determine the speed of B w.r.t A
The question implies that, we determine the relative velocity of B w.r.t A
Because both trains are moving towards one another, the required velocity is a
both trains:
This is shown below:



Answer:
the number of grains in the ball is 274,848
Explanation:
Given that;
diameter = 0.5 mm
so radius r = 0.25 mm
first we determine the volume of the ball using the following equation;
V = 4/3×πr³
we substitute
V = 4/3×π(0.25)³
V = 0.06544 mm³
Now form table 1.1 "Grain sizes" a metal with grain size number of 12 has about 4,200,000 grains/mm³
so;
Number of grains N = 0.06544 × 4,200,000
N = 274,848 grains
Therefore, the number of grains in the ball is 274,848