The bigger the object the greater the gravitational pull, so the farther away the big object is its gravitational force begins to decrease. Refer to the picture for more explanation.
It all depends on what kind of wave, and what kind of medium.
For mechanical waves, like sound and earthquakes, the speed
is determined by the mechanical properties of the medium, like
density and stiffness.
For electromagnetic waves, like radio and light, the speed is
determined by the electrical properties of the medium, like
magnetic permeability and electrostatic permittivity.
That's a big part of the reason why sound and light travel
at different speeds through air, water, and jello.
Subtract ' Z ' from each side of the equation, and the solution jumps at you from off the page.
force applied due to earth on the apple is given as

given that
m = 0.37 kg
a = 9.8 m/s^2
now we have


now as per Newton's III law equal and opposite force is applied on earth
so now we can find acceleration of Earth using same equation as we used above

here we know that
m = mass of earth
F = 3.63 N



so acceleration of earth is very small and given by above value
Answer:
It's nitrogen. Specifically, this is the alpha emission of an N-15 isotope.