Answer:
The ratio of their orbital speeds are 5:4.
Explanation:
Given that,
Mass of A = 5 m
Mass of B = 7 m
Radius of A = 4 r
Radius of B = 7 r
The orbital speed of satellite A,
......(I)
The orbital speed of satellite B,
......(I)
We need to calculate the ratio of their orbital speeds
Using equation (I) and (II)

Put the value into the formula


Hence, The ratio of their orbital speeds are 5:4.
Answer:

Explanation:
The total energy of the satellite when it is still in orbit is given by the formula

where
G is the gravitational constant
m = 525 kg is the mass of the satellite
is the Earth's mass
r is the distance of the satellite from the Earth's center, so it is the sum of the Earth's radius and the altitude of the satellite:

So the initial total energy is

When the satellite hits the ground, it is now on Earth's surface, so

so its gravitational potential energy is

And since it hits the ground with speed

it also has kinetic energy:

So the total energy when the satellite hits the ground is

So the energy transformed into internal energy due to air friction is the difference between the total initial energy and the total final energy of the satellite:

Answer:
The speed of light changes as it moves between media. This causes refraction. Angles of refraction can be calculated using known speeds or wavelengths. Beyond the critical angle, light is reflected.
Answer:
Hans Christian Oersted began a new scientific epoch when he discovered that electricity and magnetism are linked. He showed by experiment that an electric current flowing through a wire could move a nearby magnet. The discovery of electromagnetism set the stage for the eventual development of our modern technology-based world.
Explanation:
I think that the answer to that is true hope that helps