Answer:
The temperature of the Aluminium plate 44.84⁰C
Explanation:
Number of transistors = 4
Since the heat dissipated by each transistor is 12W
Total heat dissipated, Q = 4 * 12 = 48 W
Q = 48 W
Cross sectional Area of the Aluminium plate, A = 2(l * b)
l = Length of the aluminium plate = 22 cm = 0.22 m
b = width of the aluminium plate = 22 cm = 0.22 m
A =2( 0.22 * 0.22 )
A = 0.0968 m²
From the heat balance equation, Q = hAΔT
h = 25 W/m²·K
A = 0.0968 m²
ΔT = T - T(air)
T(air) = 25°C
ΔT = T - 25°C
Q = 25 * 0.0968 * ( T - 25)
Q = 2.42 (T - 25)
Substitute Q = 48 into the equation above
48 = 2.42 (T - 25)
T - 25 = 19.84
T = 25 + 19.84
T = 44.84 ⁰C
Part 1
When the solar atmosphere accumulates a lot of magnetic energy
to a point that cannot accumulate more, all that magnetic energy is suddenly released,
and with it, a lot of radiation. So much, that in fact it covers all of the
electromagnetic spectrum; from radio waves to gamma rays. That burst of
radiation is called a solar flare. In a single solar flare the amount of
radiation released is millions of times greater than all the nuclear bombs in
the face if the earth exploding together. Lucky for us, most of the high-energy
radiation dissipates before reaching the Earth, and the radiation that do reach
us, is deflected by the Earth’s magnetic field.
Part 2
1. Not all the radiation
of solar flares that reach the Earth is deflected by its magnetic field; some
of them reach us and charges the upper atmosphere with ionized particles. Those
particles react with the gases in the atmosphere and produce a light; that
light is what we call Auroras borealis or southern nights; One the most beautiful
natural spectacles in earth, who thought Auroras begin their lives as deadly
solar flares.
2. Solar flares
contain a lot of high-energy radiation that is extremely dangerous for our
electronic devices; when they reach the Earth, they can damage sensible
electronics like satellites. A very powerful solar flare could even damage all
the electronic devices on the surface of the Earth.
Answer:
The answer to your question is
Explanation:
Data
mass = 0.5kg
T1 = 35
T2 = ?
Q = - 6.3 x 10⁴ J = - 63000 J
Cp = 4184 J / kg°C
Formula
Q = mCp(T2 - T1)
T2 = T1 + Q/mCp
Substitution
T2 = 35 - 63000/(0.5 x 4184)
T2 = 35 - 63000/2092
T2 = 35 - 30.1
T2 = 4.9 °C