A wire delivers 120 C of charge in 40 s.
What is the current in the wire?
30A
80A
16A
48A

3 A

Explanation:

Charge is a product of current and time, expressed as Q=It where Q is charge in Coulombs, I is current in Amperes and t is time taken in seconds. Making I the subject of the formula then

Substituting 120 C for charge and 40 s for t then

From the choices given, it appears that time should have been 4 s to get option A or alternatively charge should have been 1200 C

in simple terms, the principle states that the buoyancy force on an object is equal to the weight of the fluid displaced by the object, or the density of the fluid multiplied by the submerged volume times the gravitational acceleration, g. this is also known as upthrust.