Electric field and electric potential

The graph shows the electric potential some distance away from a conductor. What is the graph of the electric field around that conductor?

• 
• 
• 
• 

What is the electric potential at a distance of 50 cm away from a point charge of +2.0 nC?

ε₀ = 8.854 × 10⁻¹² F m⁻¹

• 3.6 V

• 36 V

• 7.2 V

• 72 V

The radius (distance from nucleus) of a hydrogen atom is 120 pm. What is the electric field strength at that distance from the nucleus?

e = 1.60 × 10⁻¹⁹ C

ε₀ = 8.854 × 10⁻¹² F m⁻¹

• 1.00 × 10⁻¹⁰ N/C

• 1.00 × 10⁻¹¹ N/C

• 1.30 × 10⁻¹⁰ N/C

• 1.30 × 10⁻¹¹ N/C

An electric field strength of 10 N C⁻¹ is measured around a point charge at a distance of 10 cm. What is the electric field strength around the same point charge at a distance of 20 cm away?

• 2.5 N C⁻¹

• 5.0 N C⁻¹

• 20 N C⁻¹

• 40 N C⁻¹

At point X which distance is r₁ from a point charge, the electric potential is V_X. At point Y which distance is r₂ from the same point charge, the electric potential is V_Y.

How much work is done to bring a proton (with a charge of e) from point X to point Y in joules?

• e(V_X−V_Y)

• e(V_Y−V_X)

• e(V_X−V_Y)/r

• e(V_Y−V_X)/r

What is the electric field strength and electric potential inside a hollow charged conductor sphere of radius r and charge q at a distance of x from the centre of sphere?

• 0, kq/r

• 0, kq/x

• kq/r², kq/r

• kq/x², kq/x

The work required to move a charge from infinity to a point in an electric field is called ...

• electric field strength

• electric potential

• electric potential energy

• electric force

At what distance is the electric potential around a negative point charge is at its greatest value?

• 0

• ∞

• radius of the charge

• cannot be determined

Potential graph between two point charges, Q₁ dan Q₂, are shown. Which of the following statements is true?

• Q₁ is positive, Q₂ is negative

• Q₁ is positive, Q₂ is positive

• Q₁ is negative, Q₂ is positive

• Q₁ is negative, Q₂ is negative

Potential graph between two point charges, Q₁ dan Q₂, are shown. At what point along r axis, is electric field strength = 0?

• 1

• 2

• 3

• cannot be determined