This is just a simple problem finding out the outer surface charge, the inner surface charge and the net charge. Net charge by definition means the difference between two charges. In this case, the formula that is applicable here is outer surface charge = total net charge - inner cavity surface charge. Since we are given already with the net charge equal to 12.0 x10-6 C and the inner charge magnituude f 3.7 x10-6 C, the the total charge must be outer charge is +10x10(-6)) - (-3.0x10(-6)) = +1.3x10(-5) C.
Charges are measured in coloumbs and most likely exist on surfaces of entities like particles, walls etc.
Answer:
Magnitude of vector A = 0.904
Explanation:
Vector A , which is directed along an x axis, that is

Vector B , which has a magnitude of 5.5 m


The sum is a third vector that is directed along the y axis, with a magnitude that is 6.0 times that of vector A 
Comparing we will get

Substituting in 

So we have

Magnitude of vector A = 0.904
Answer:
Explanation:
Given
Distance = 4.0m
Time = 5.0 mins = 300secs
Required
Average speed
Average speed = Distance/Time
Average speed = 4.0/300
Average speed = 0.01333m/secs
Hence the average speed of the snail is 0.01333m/s
R = U : I. U is in Voltage and I is in Ampère. That gives you R = 36 : 8 = 4,5 Ohm