Answer:
Decreased by a factor of 4.5
Explanation:
"We have Newton formula for attraction force between 2 objects with mass and a distance between them:

where
is the gravitational constant on Earth.
are the masses of the object and Earth itself. and R distance between, or the Earth radius.
So when R is tripled and mass is doubled, we have the following ratio of the new gravity over the old ones:




Since
and 

So gravity would have been decreased by a factor of 4.5
Answer:
The answer is "between 20 s and 30 s".
Explanation:
Calculating the value of positive displacement:


Calculating the value of negative displacement upon the time t:




That's why its value lie in "between 20 s and 30 s".
Answer:
The airplane should release the parcel
m before reaching the island
Explanation:
The height of the plane is
, and its speed is v=150 m/s
When an object moves horizontally in free air (no friction), the equation for the y measured with respect to ground is
[1]
And the distance X is
x = V.t [2]
Being t the time elapsed since the release of the parcel
If we isolate t from the equation [1] and replace it in equation [2] we get

Using the given values:

x =
m
Answer:
Mass
Explanation:
Inertia is essentially an object's tendency to stay in motion or at rest unless it is forced to do otherwise (pun intended). It only makes sense to me that mass would best quantify an object's inertia, because an object with more mass would be harder to move and/or stop from moving.
Answer:
In hot gases , the atoms keeps colliding with each other and sometimes the energy liberated during collision takes the electron to a higher level,thus, .The object is a cloud of hot gas and finally the electron returns back emitting photon