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 momentum of block B = 27 Kg m/s
Explanation:
Given,
The initial momentum of block A, MU = 15 Kg m/s
The final momentum of block A, MV = -12 Kg m/s
Consider the block B is initially at rest.
Therefore, the initial momentum of block B, mu = 0
According to the laws of conservation of linear momentum, the momentum of the body before impact is equal to the momentum of the body after impact.
<em> MU + mu = MV + mv</em>
15 + (0) = (-12) + mv
mv = 15 + 12
= 27 Kg m/s
Hence, the momentum of the block B after impact is, mv = 27 Kg m/s
Answer:
B). to the right
Explanation:
Since the direction of magnetic field is into the page
So here we know that

now the velocity is from bottom to top
so we have

now the force on the moving charge is given as

now we have


so force will be towards Right