Answer:
D. Cooler
Explanation:
The Sun's surface has a temperature ranging from 6 000 Kelvin, thus it is very hot. The radioactive reaction in the core of the Sun is a nuclear fusion reaction. This reaction ensures continuous release of high energy from the surface of the Sun.
But during the reaction, some parts becomes cooler than other parts on its surface. Which is due to the release of high amount of energy into space. The Sun's spot can be found in the cooler part of the Sun.
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
It is true. Time is always measured in seconds.
law of electromagnetic induction hope this helps