Answer:
a) The sign of the charge is positive.
b) The magnetic force on the particle is 0.050 newtons.
Explanation:
The magnetic force F on a moving charge with velocity v passing through a magnetic field B is:
(1)
a)
Because it is a cross product, we can find the direction of the force using the right-hand rule, that is too the direction of the movement. We have two possibilities here because the velocity vector and magnetic field are perpendicular: the particle deflects towards east or toward west, which depends on the charge of the particle. Note that if you put your right hand fingers, except thumb, pointing towards north (direction of velocity) and later close them in the direction of the magnetic field, if you maintain your thumb perpendicular to this movement it will point towards east (See figure), so that will be de direction of the force if the charge is positive, but if the charge is negative, the direction will be opposite (towards west). So the charge has to be positive to deflects towards east.
b)
Now by 1:

Answer:
295.42 N
Explanation:
From Newton's law of universal gravitation.
F = Gmm'/r².................. Equation 1
Where F = Gravitational force, G = Universal constant, m = mass of the human, m' = mass of mass, r = radius of mass.
Given: m = 80 kg, m' = 6.4×10²³ kg, r = 3.4×10⁶ m.
Constant: G = 6.67×10⁻¹¹ Nm²/Kg²
Substitute into equation 1
F = 6.67×10⁻¹¹(80)(6.4×10²³ )/( 3.4×10⁶)²
F = 3415.04×10¹²/(11.56×10¹²)
F = 3415.04/11.56
F = 295.42 N
Hence the gravitational force = 295.42 N
Answer: 1. decreasing the mass of both objects
2. decreasing the mass of one of the objects
3. increasing the distance between the objects
Explanation: Hope that helped! (: