Answer:
(a) Ratio of mean density is 0.735
(b) Value of g on mars 0.920 
(c) Escape velocity on earth is 
Explanation:
We have given radius of mars 
and radius of earth 
Mass of earth 
So mass of mars 
Volume of mars 
So density of mars 
Volume of earth 
So density of earth 
(A) So the ratio of mean density 
(B) Value of g on mars
g is given by 
(c) Escape velocity is given by
Answer:
it just pulls them at the same time
Explanation:
False, the spinning coil of wire that moves the cone in a speaker does not produces sound.
<u>Explanation</u>:
The wire coil is an electromagnet that is fixed to speaker cone. A normal magnet attached to the back of the speaker cone.When audio is sent in the form of short bursts of electric current to the speaker cone through the wire.
A magnetic field is induced when electric current allowed to pass through the coil. This magnetic field is repelled by the other magnet. This repulsion cause the cone to move forward. In the absence of electric current in the coil, the cone moves backward.
Thus sound waves are produced due to the resulting rarefaction and compression. So it is not the spinning coil of wire but he permanent magnet that produces the sound.
