A small planet is discovered to have a layer of electrically charged dust floating at 1000 m above the surface because of the balance between the gravitational forces and electrical forces exerted on the dust by the planet. If the dust layer is moved to 2000 m above the surface, what will happen to the dust, and why?
The dust will fall because the gravitational force will be stronger than the electrical force,
А
B
The dust will rise because the gravitational force will be weaker than the electrical force.
с
The dust will continue to float because the gravitational force will still balance the electrical force,
D
What will happen to the dust cannot be determined without knowing the amount of dust moved

a charge 3q is at the origin, and a charge −2q is on the positive x axis at x=a. part a where on the x-axis would you place a third charge so it would experience no net electric force? enter an expression for the exact answer, which will involve a square-root sign. (do not enter an approximate decimal answer.)

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min

3. dark matter

empty space could also be a simple vacuum