Answer:

Explanation:
We are given that
Diameter of wire=d=4.12 mm
Radius of wire=r

Current=I=8 A
Drift velocity=
We have to find the density of free electrons in the metal
We know that
Density of electron=
Using the formula
Density of free electrons=
By using Area of wire=

Density of free electrons=
Answer:
<h2> r=mv/Be</h2>
Explanation:
If a positive charge enters a magnetic field at 90 degrees the charge is deflected in a circular path by a force that acts perpendicular to it in line with Flemings right-hand rule
to derive the radius of the path of the charge we apply
F= mv^2/r=Bev
where
m= mass of the electronic charge
e=charge
B=magnetic field
v=average speed
r=radius
rearranging we have
r=mv^2/Bev
r=mv/Be
The nucleus is the core of an atom which is made up of protons and neutrons. Every single type of atom has a dense center and the majority of the mass is located in here.
Answer:
the angle made by this ray with normal will be 45°
Explanation:
given,
refractive index of crown glass = 1.52
refractive index of the water = 1.33
ray of light in water strikes glass at 45°
angle subtended by the light when it reenter water = ?
When light enter in the glass from the water it get bend toward normal because refractive index of glass is more than water.
And when ray comes out of the glass it is parallel to the initial light ray.
hence, the angle made by this ray with normal will be 45°

You just do the calculations.