Answer:
Their speed in a vacuum is a constant value.
Explanation:
Electromagnetic waves consits of oscillations of electric field and magnetic field. The oscillations of these fields occur in a direction perpendicular to the direction of propagation of the waves, so they are transverse wave. Electromagnetic waves, contrary to mechanical waves, do not need a medium to propagate, so they can also travel through a vacuum. In a vacuum, their speed is constant and has always the same value, the speed of light:
Given:
Total distance = 1000 kilometer
Total time = 5 hours
To find:
Average speed = ?
Formula used:
=
Where = average speed
s = total distance
t = total time
Solution:
Average speed of the jet is given by,
=
Where = average speed
s = total distance
t = total time
=
= 200 km/ h
Thus, average speed of the jet is 200 km/h.
Hence, Option (A) is correct.
The four inner planets share several features in common.
(Mercury, Venus, Earth and Mars)
They are called terrestrial planets because they have solid, rocky surfaces roughly similar to desert and mountainous areas on the earth.
The property that compares the mass of an object with its volume is density.