Answer:
The reason for phonograph installation is to provide information about humans to interstellar aliens.
Explanation:
Phonographs are archaic forms of gramophone which are able to record and reproduce sound.Phonographs were used in early days in voyagers to help transmit information about humans to nearby alien species in space.
Answer:
The diameter of the camera aperture must be greater than or equal to 1.49m
Explanation:
Let the distance separating two objects, x = 6.0 cm = 0.06 m
The distance between the observer and the two objects, d = 160 km = 160000 m
Let ∅ = minimum angular separation between the two objects that the satellite can resolve
tan( ∅) = x/d
Since there is minimum angular separation, tan( ∅) ≈∅
∅ = x/d
∅ = 0.06/160000
∅ = 3.75 * 10⁻⁷rad
For the satellite to be able to resolve the objects,
D ≥ 1.22λ/∅
λ = 560 nm = 560 * 10⁻⁹
D ≥ 1.22 * (560 * 10⁻⁹)/(3.75 * 10⁻⁷)
D ≥ 149.33 * 10⁻² m
D ≥ 1.49 m
Answer:
The force on the grass hopper is equal and opposite to the force on the wind shield.
Explanation:
It is a known fact every action has an equal and opposite reaction. Here the action force is the grasshopper hitting the windshield.
The reaction force is the force exerted by the windshield on the grasshopper.
If the force of windshield on the grasshopper is more, grasshopper would have been thrown away. If the grasshopper's force on the windshield is greater, the windshield would have broken.
But here these constitute equal and opposite action-reaction pair of forces and so the grasshopper is able to repeatedly strike the windshield.
Answer: option c: It orbits beyond the Earth's atmosphere to avoid scattering of light.
Explanation:
Hubble space telescope orbits Earth and sends images of distant objects. The images formed by Hubble are better than the optical telescopes used on land. This is because the Hubble telescope is a space telescope. Light from the distant objects when reaches the land telescopes transmits through atmosphere, where scattering occurs. Some the light rays bounce back. This is avoided by the space telescope Hubble.
The direction of the friction force is the same than the movement, but its sense is the opposite.
