At what temperatures does the rms speed of (a) H2(molecular hydrogen) and (b) O2 (molecular oxygen) equalthe escape speed from Earth (escape speed=11.2 km/s) ? At whattemperature does the rms speed of (c) H2 and (d)O2 equal the escape speed from the Moon (where thegravitational acceleration at the surface has magnitude0.16g)? Considering the answers to parts (a) and (b), shouldthere be much (e) hydrogen and (f) oxygen high in Earth's upperatmosphere, where the temperature is about 1000 K?The answers are:(a) 1.0 × 104 K;(b) 1.6 × 105 K;(c) 4.4 × 102 K;(d) 7.0 × 103 K;(e) no;(f) yes

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.

false

hope this : d

the moving of the box is a result of centripetal force. think of that  as a car or a truck in this case creates a turn, the force of friction performing upon the turned wheels of the car runs centripetal force obligatory for circular motion for the things inside it.