Answer:
Four charges of equal magnitude sitting at the vertices of a square
Explanation:
We can arrive at such a situation by thinking of a simple example first, a configuration of two charges. The force acting on the middle point of a straight line joining the two points(charges) will be zero. That is, the net Electric field will be zero as they cancel out being equal in magnitude and opposite in direction.
Now, we can extend this idea to a square having charge q at each vertex. If we put 'p' at the geometric center, we can see that the Electric fields along the diagonals cancel out due to the charges at the diagonally opposite vertices(refer to the figure attached). Actually, the only requirement is that the diagonally opposite charges are equal.
We can further take this to 3 dimensions. Consider a cube having charges of equal magnitude at each vertex. In this case, the point 'p' will yet again be the geometric center as the Electric field due to the diagonally opposite charges will cancel out.
Magnets facing the same way <span />
Answer:
B)
The magnitude of induced emf in the conducting loop is 0.99 mV.
Explanation:
Rate of increase in magnetic field per unit time = 0.090 T/s
Area of the conducting loop = 110 cm^2 = 0.0110 m^2
Electromagnetic induction is the production of an emf or voltage in a coil of wire due to a changing magnetic field through the coil.
Induced e.m.f is given as:
EMF = (-N*change in magnetic field/time)*Area
EMF = rate of change of magnetic field per unit time * Area
EMF = 0.090 * 0.0110
EMF = 0.00099 V
EMF = 0.99 mV
Work=applied Force x distance
= 1275 x 26
=33150 Joules
Answer:
Option C
Explanation:
According to the question:
Force exerted by the team towards south, F = 10 N
Force exerted by the opposite team towards North, F' = 17 N
Net Force, 

Thus the force will be along the direction of force whose magnitude is higher
Therefore,
towards North