B.) Venus and Uranus
All of the planets move in an eastward direction except Venus and Urunus
Answer:
Explanation:
Consider two particles are initially at rest.
Therefore,
the kinetic energy of the particles is zero.
That initial K.E. = 0
The relative velocity with which both the particles are approaching each other is Δv and their reduced masses are
now, since both the masses have mass m
therefore,
= m/2
The final K.E. of the particles is
Distance between two particles is d and the gravitational potential energy between them is given by
By law of conservation of energy we have
Now plugging the values we get
This the required relation between G,m and d
Answer: C. good reflector of heat
Explanation:
In space, sunlight transfers heat by radiation to objects and bodies and this includes satellites and astronauts. In addition, although the peak of the sun's emission is in the visible region of the electromagnetic spectrum, a part is also emitted in infrared (transferring thermal energy or heat) and ultraviolet (especially in the upper part of the Earth's atmosphere).
That is why in space missions, objects and many satellites are covered by thin layers or sheets that reflect this thermal energy and thus avoid damaging the equipment due to high temperatures.
In this sense, among the reflective materials used are aluminum, silver, copper and gold; the latter being the most used because it does not corrode or oxidize (unlike silver and copper) and is more malleable than aluminum.
On the other hand, <u>astronauts are also vulnerable to the effects of infrared radiation, especially their eyes</u>, since the human eye has no receptors in the infrared spectrum. <u>That is why the astronaut's helmet visor is covered with a thin layer of gold to avoid the dangerous effects of solar radiation.</u>
The airplane's speed relative to the ground is
√ (100² + 25²)
= √ (10,000 + 625)
= √ 10,625
= 103.08 km/hr .
The angle of its velocity north of west is
the angle whose tangent is (25/100)
arctan(25/100) = 14° north of west .
(bearing = 284°)
The solution would be like this for this specific problem:
Given: 5973 K
λ_peak = 2.898 / 5973 K
= 0.00048518 mm = 0.48518 μ = 4851.8 Ậ
Polaris emits peak radiation at 485 nm wavelength.
To add, Polaris, commonly the North Star or Pole
Star, is the brightest star in the constellation of Ursa Minor.