AS Physics Electric Circuits

Kirchoff's First Law states

• the sum of the currents entering any junction in an electric circuit must equal the sum of the currents leaving that junction

• the sum of the charges entering any junction in an electric circuit must equal the sum of the charges leaving that junction

• the sum of the emfs entering any junction in an electric circuit must equal the sum of the pds leaving that junction

• none of these

Kirchoff's second law states

• in any closed loop in an electric circuit the algebraic sum of the electromotive forces in the loop is equal to the algebraic sum of the potential differences in that loop

• in any closed loop in an electric circuit the vector sum of the electromotive forces in the loop is equal to the vector sum of the potential differences in that loop

• in any closed loop in an electric circuit the algebraic sum of the currents in the loop is equal to the algebraic sum of the potential differences in that loop

• none of these

Select all true statements

• Kirchoff's second law depends on the conservation of energy principle

• Kirchoff's first law depends upon the conservation of charge

• Kirchoff's second law depends on the conservation of charge principle

• Kirchoff's first law depends upon the conservation of energy

Select all true statements

• In the dark an LDR has very high resistance in the MΩ range

• The output p.d. will be low in the dark

• In the light an LDR has very high resistance in the MΩ range

• The output p.d. will be high in the dark

Select all true statements

• This is a thermistor circuit symbol

• This component is a semiconductor

• This component resistance decreases as temperature increases

• This component resistance decreases as temperature decreases

Select all true statements

• This component is a light emitting diode

• It only allows current to flow one way

• It is temperature dependent

• It depends on light intensity

• i1 + i5 +i4 = i2 + i3

• i1 + i5 +i3 = i2 + i4

• i5 + i2 +i4 = i1 + i3

• i1 + i5 = i2 + i3 + i4

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Which equations are correct?

• ε₁ - i₁R₁ - i₂R₂ = 0

• ε_{1 +} ε₂ + i₃R₃ - i₂R₂ = 0

• ε₁ - i₂R₁ - i₂R₂ = 0

• ε₁ - ε₂ - i₃R₃ + i₂R₂ = 0

Tags

NGSS.HS-PS2-5

NGSS.HS-PS3-5

For this circuit select the correct statements

• i₁ = 2 A

• i₃ = 8 A

• i₂ = 6 A

• i₂ = i₁ + i₃

• V₁ = 17 V

• V₃ = 15 V

• V₃ = 4.5 V

• V₁ = 3.0 V