Answer:
compared to the incident angle, the refracted angle is 45.56⁰
Explanation:
From Snell's law;
n₁sin(I) = n₂sin(r)
Where;
n₁ is the refractive index of light in medium 1 = 1.2
n₂ is the refractive index of light in medium 2 = 1.4
I is the incident angle
r is the refractive angle

I = 56.439⁰
Applying snell's law

Therefore, compared to the incident angle, the refracted angle is 45.56⁰
It only occurs when there is an electric current
Answer:
The ratio of the diameter of iron to Cu is;

Explanation:
R=(ρL)/A
- R is resistance,
- L is length,
- A is area,
- ρ is resistivity
- d is diameter
from the question the two materials have the same resistance per unit length.

for iron =
for copper
This means we can equate ρ/A for both materials.

re-arranging the equation we have,





Answer:
As voltage increases, current increases and resistance stays the same
.
Explanation:
Ohm's law gives the relationship between the voltage, resistance, and current. The mathematical form of Ohm's law is given by :

R is resistance
I is current
V is voltage
So, as voltage increases, current increases and resistance stays the same. The correct option is (A).
A).
It would decrease because the speed of sound and temperature are proportional.