If you quadrupled the mass and tripled the radius of a planet, by what factor would gg at its surface change

4/3

Explanation:

We already know aforehand that the acceleration due to gravity on the surface of a planet is given as

GM/r²,

Now, if the mass is quadrupled, we would have

G4M/r²,

If the radius is then tripled, we would have again

G4M/3r²

And that is what we have, now, to get the factor that the acceleration changes is simply to compare it with the primary equation

HM/r² = G4M/3r²

And thus, we find out that the factor is 4/3 or 1.333

Explanation:

Doppler effect: It is the phenomenon in which there is relative motion between the source and the observer or the source and the listener. There is an apparent change in the frequency.

When the observer and the source are moving towards each other then the frequency increases.

When the observer and the source are moving away from each other then the frequency decreases.

The expression of the speed of the wave in terms of the frequency is as follows;

Here, v is the speed of the wave, f is the frequency of the wave and is the wavelength of the wave.

From the above relation, it can be concluded that speed of the sound is directly proportional to the frequency of the wave.

The magnitude of the Doppler shift increases when the velocity of the sound source is increased.