Answer: +2 e
Explanation: Net charge of a system is sum of charges on all the constituents of the system.
The system contains two spheres. Charge on one sphere is:
q₁ = +6 e
Charge on the second sphere is:
q₂ = -4 e
Net charge of the system is:
q = q₁ + q₂
q = +6 e + (-4 e) = + 2 e
Thus, the net charge of system is +2 e.
Answer:
The correct option is;
B. Subtract vectors A from C;
= 12 N
Explanation:
The given parameters are;
The weight of the dresser = 250 N
The force applied by the man = 20 N = C
The frictional force provided by the carpet = 8 N = The component of the weight resisting motion = A
Therefore, the net force tending to put the dresser in motion,
, is given as follows;
= The force applied by the man, C - The frictional force provided by the carpet which is the component of the weight resisting motion, A
= C - A = 20 N - 8 N = 12 N
= 12 N
The resulting net force,
= 12 N.
Explanation:
Given that,
Radius of the circular loop, r = 3.5 cm = 0.035 m
(a) During a 0.12-s time interval, the magnitude of the field increases uniformly from 0.2 T to 0.5 T. Due to the change in the magnetic field, an emf will induced in it. The magnitude of induced emf is given by :

So, the magnitude of the emf induced in the loop during the time interval is
.
(b) The negative sign shows that the direction of induced emf in the loop is in anitclockwise direction.