Electric Current & Direct Current Circuits

Define electric current

• the total charge, Q flowing through the area per unit time, t.

• the total current, I flowing through the area per unit time, t.

• the rate of capacitance flow through a conductor.

• the rate of current flow through a conductor

1 ampere of current is defined as ......

• one coulomb of current passing through the surface area in one second.

• one coulomb of charge passing through the conductor in one second

• one coulomb of charge passing through the surface area in one second

• one coulomb of currrent passing through the conductor in one second.

Resistivity is defined as .....

• the capacitance of a unit length per unit cross-sectional area of the material

• the resistance of a unit length per unit cross-sectional area of the material

• the capacitance of a unit cross-sectional area per unit length of the material

• the resistance of a unit cross-sectional area per unit length of the material

What type of quantity does the current belongs to?

• a base and vector quantities

• a base and scalar quantities

• a derived and vector quantities

• a derived and scalar quantities

From the equation, we know that the resistance of a conductor depends on..?

• length of conductor

• cross sectional area

• type of material

• volume of the wire

State Ohm's Law.

• the potential difference across a metallic conductor is proportional to the resistance flowing through it if its temperature is constant.

• the resistance across a metallic conductor is proportional to the current flowing through it if its temperature is constant.

• the potential difference across a metallic conductor is proportional to the current flowing through it if its temperature is constant.

• the current across a metallic conductor is proportional to the potential difference flowing through it if its temperature is constant.

Which equation defines Ohm's Law?

• V=IV

• R=VI

• I=VR

• V=IR

If current flow in a bulb is 1.5A. What is the charge flow in 5 minutes?

• 4.5x10exp-2 C

• 4.5x10exp-2 A

• 2.4x10exp-2 C

• 2.4x10exp-2 A

What is the effective resistance for two resistors that each has 15ohm resistance and they are connected in parallel?

• 7ohm

• 7.5ohm

• 7.2ohm

• 7.25ohm

A resistor of 5ohm is connected in series with two other resistors that is connected in parrallel, each has 3ohm resistance. Calculate the effective resistance for this combination of resistors.

• 60ohm

• 12ohm

• 6.5ohm

• 13.45ohm