Satellites are placed into orbit at least 150 km above Earth's surface to be above the atmosphere.
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
Answer:
The term "aerobic" refers to the body's ability to provide energy through the use of oxygen. The term anaerobic refers to the body's ability to provide energy without the use of oxygen.
An example of an aerobic exercise is swimming. An example of an anaerobic exercise is sprinting.
Explanation:
Answer:
1) is<u> positive.</u>
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2)
Explanation:
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Part 1:</u></h2>
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The charged rod is held above the balloon and the weight of the balloon acts in downwards direction. To balance the weight of the balloon, the force on the balloon due to the rod must be directed along the upwards direction, which is only possible when the rod exerts an attractive force on the balloon and the electrostatic force on the balloon due to the rod is attractive when the polarities of the charge on the two are different.
Thus, In order for this to occur, the polarity of charge on the rod must be positive, i.e., is <u>positive.</u>
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Part 2:</u></h2>
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<u>Given:</u>
- Mass of the balloon, m = 0.00275 kg.
- Charge on the balloon,
- Distance between the rod and the balloon, d = 0.0640 m.
- Acceleration due to gravity,
In order to balloon to be float in air, the weight of the balloom must be balanced with the electrostatic force on the balloon due to rod.
Weight of the balloon,
The magnitude of the electrostatic force on the balloon due to the rod is given by
is the Coulomb's constant.
For the elecric force and the weight to be balanced,
Answer:
An object may become extinct due to the lack of quantity of the object and the object no longer exists so it is now extinct.