Answer:
the maximum intensity of an electromagnetic wave at the given frequency is 45 kW/m²
Explanation:
Given the data in the question;
To determine the maximum intensity of an electromagnetic wave, we use the formula;
=
ε₀cE
²
where ε₀ is permittivity of free space ( 8.85 × 10⁻¹² C²/N.m² )
c is the speed of light ( 3 × 10⁸ m/s )
E
is the maximum magnitude of the electric field
first we calculate the maximum magnitude of the electric field ( E
)
E
= 350/f kV/m
given that frequency of 60 Hz, we substitute
E
= 350/60 kV/m
E
= 5.83333 kV/m
E
= 5.83333 kV/m × (
)
E
= 5833.33 N/C
so we substitute all our values into the formula for intensity of an electromagnetic wave;
=
ε₀cE
²
=
× ( 8.85 × 10⁻¹² C²/N.m² ) × ( 3 × 10⁸ m/s ) × ( 5833.33 N/C )²
= 45 × 10³ W/m²
= 45 × 10³ W/m² × (
)
= 45 kW/m²
Therefore, the maximum intensity of an electromagnetic wave at the given frequency is 45 kW/m²
Answer : 
Explanation :
Given that
Radius of sphere 
The distance between the centers of the two spheres is

The charge of the sphere 
The magnitude of the repulsive force between the charges pushing them a part is
Using coulomb law




Hence, this is the required solution.
Water<span> is </span>denser<span> than </span>alcohol<span> because its molecules can pack tightly together, which means that it has </span>more<span> mass in the same volume than </span>alcohol<span> </span>
Answer:
c
. slower and started moving in place.
Explanation:
Matter can exist generally in three phases, as a solid, liquid or gas. But it can be transformed from one phase to another by the removal or application of heat energy.
The water was initially in a liquid form in the sealed tank until energy was transferred out of the substance. Thus, this causes a change of state in which the water turns to a solid. Whereby during the process, the molecules of the water moved slowly until they are fixed at a point, and vibrates individually at their individual point.
Therefore the molecules of water moved slower and stated moving in place (i.e vibrating at a point). The water turns to an ice.