The mass of the astronaut is still 65 kilograms. Mass is constant or doesn't change no matter where you are.
We're told that the planets have EQUAL MASS.
If that's true, then the strength of the gravitational forces between
each planet and the star depends only on the distance between
them ... the farther a planet is from the star, the smaller the
gravitational forces are IF we're talking about planets with
equal masses.
Planet-X is closer to the star, and Planet-Y is farther from it.
From this we know that the gravitational forces between the
star and Planet-X are greater, and the forces between the star
and Planet-Y are smaller.
'A' says this.
'B' is totally absurd, because it talks about gravity repelling things.
'C' says exactly the opposite for the two planets.
'D' says that distance doesn't matter. We know this is absurd,
simply because we're never pulled toward Jupiter in our daily life.
By reading the fine details of the question, carefully and analytically, I have determined that there's no list of modifications to choose from.
The strength of the magnetic field of a solenoid depends on the electric current in its coil windings, the number of wire turns in its coil windings, and the material in its core.
In order to <em>DE</em>crease the strength of its magnetic field, any one or more of these steps could do the job:
-- DEcrease the electric current in its coil windings. This can be accomplished by decreasing the voltage of the power source that energizes the coil, and/or increasing the resistance of the wire in the coil.
-- DEcrease the number of wire turns in the coil.
-- If the solenoid has anything in its core, change the core to something with a lower magnetic 'permeability'. An Iron core will produce the greatest magnetic field strength. Air, vacuum, or NO core will produce the lowest magnetic field strength.
Answer: 5.12x10∧-4N
Explanation:
Force = I B L
L = 6.4m
Let Current (I) I₁ = I₂= 14A
Distance of the wire = 42cm = 0.42m
BUT
B = μ₀I / 2πr
=(2X10∧-7 X 12) / 0.42
B =5.714×10∧-6T
Force = I B L
Force = 14x [5.714×10-6]×6.4
Force = 5.12x10∧-4N
