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 range is maximum when the angle of projection is 45 degree.
Explanation:
The formula for the horizontal range of the projectile is given by

The range should be maximum if the value of Sin2θ is maximum.
The maximum value of Sin2θ is 1.
It means 2θ = 90
θ = 45
Thus, the range is maximum when the angle of projection is 45 degree.
If the angle of projection is 0 degree
R = 0
It means the horizontal distance covered by the projectile is zero, it can move in vertical direction.
If the angle of projection is 30 degree.

R = 0.088u^2
If the angle of projection is 45 degree.

R = u^2 / g
Answer:
Hydrogen has one electron and one proton
Answer:
6.78 X 10³ N/C
Explanation:
Electric field near a charged infinite plate
= surface charge density / 2ε₀
Field will be perpendicular to the surface of the plate for both the charge density and direction of field will be same so they will add up.
Field due to charge density of +95.0 nC/m2
E₁ = 95 x 10⁻⁹ / 2 ε₀
Field due to charge density of -25.0 nC/m2
E₂ = 25 x 10⁻⁹ / 2ε₀
Total field
E = E₁ + E₂
= 95 x 10⁻⁹ / 2 ε₀ + 25 x 10⁻⁹ / 2ε₀
= 6.78 X 10³ N/C
<h2>The hiker will go up to 850 m on the hill</h2>
Explanation:
The total energy gained by the hiker = 140 x 4186 J
This energy is consumed in the potential energy acquired , while climbing up the hill.
The potential energy P.E = mass of hiker x acceleration due to gravity x height
Thus
140 x 4186 = 69 x 10 x h
or h =
= 850 m
If the 20% of the total energy is used
the height h₀ =
= 170 m