A. Space, time and motion

A.1 Kinematics

A.2 Forces and momentum

A.3 Work, energy and power

A.4 Rigid body mechanics

A.5 Galilean and special relativity

B. The particulate nature of matter

B.1 Thermal energy transfers

B.2 Greenhouse effect

B.3 Gas laws

B.4 Thermodynamics

B.5 Current and circuits

C. Wave behaviour

C.1 Simple harmonic motion

C.2 Wave model

C.3 Wave phenomena

C.4 Standing waves and resonance

C.5 Doppler effect

D. Fields

D.1 Gravitational fields

D.2 Electric and magnetic fields

D.3 Motion in electromagnetic fields

D.4 Induction

E. Nuclear and quantum physics

E.1 Structure of the atom

E.2 Quantum physics

E.3 Radioactive decay

E.4 Fission

E.5 Fusion and stars

S Skills in Physics

S1.1 Experimental techniques

S1.2 Technology

S1.3 Mathematics

S2.1 Exploring and designing

S2.2 Collecting and processing data

S2.3 Concluding and evaluating

IB Physics HL D.2 Electric and magnetic fields Question Bank

[Maximum number: 2]

Ion-thrust engines can power spacecraft. In this type of engine, ions are created in a chamber and expelled from the spacecraft. The spacecraft is in outer space when the propulsion system is turned on. The spacecraft starts from rest.

The mass of ions ejected each second is $6.6 \times 10^{-6} \mathrm{~kg}$ and the speed of each ion is $5.2 \times 10^{4} \mathrm{~m} \mathrm{~s}^{-1}$ . The initial total mass of the spacecraft and its fuel is 740 kg . Assume that the ions travel away from the spacecraft parallel to its direction of motion.

(a)

In practice, the ions leave the spacecraft at a range of angles as shown.

[ 2 ]

(i)

Outline why the ions are likely to spread out.

[ 2 ]

[Maximum number: 1]

Two charged parallel metal plates, X and Y , are separated by a distance of $2.0 \mathrm{~m} . \mathrm{X}$ is at a potential of -150 V and Y is at a potential of +150 V .

Point P is midway between X and Y . Which of the following gives the electric field strength at point P ?

$150 \mathrm{Vm}^{-1}$ to the right

$150 \mathrm{Vm}^{-1}$ to the left

$300 \mathrm{Vm}^{-1}$ to the right

$300 \mathrm{Vm}^{-1}$ to the left

[Maximum number: 1]

Which diagram shows a correct equipotential line due to two point charges X and Y of opposite sign?

(a)

Two identical conducting spheres X and Y that carry positive charges are separated by a centre-to-centre distance of 24.0 cm in a vacuum. The charge on X is 9 Q and the charge on Y is Q. Point R is 6.0 cm from the centre of Y, as shown.

The resultant electric field at R is $32.6 \mathrm{MNC}^{-1}$ . Determine Q, giving an appropriate unit.

[ 2 ]

[Maximum number: 5]

A vertical wall carries a uniform positive charge on its surface. This produces a uniform horizontal electric field perpendicular to the wall. A small, positively-charged ball is suspended in equilibrium from the vertical wall by a thread of negligible mass.

(a)

The centre of the ball, still carrying a charge of $1.2 \times 10^{-6} \mathrm{C}$ , is now placed 0.40 m from a point charge Q . The charge on the ball acts as a point charge at the centre of the ball.
P is the point on the line joining the charges where the electric field strength is zero. The distance PQ is 0.22 m .

[ 5 ]

(i)

Calculate the charge on Q. State your answer to an appropriate number of significant figures.

[ 3 ]

(ii)

Outline, without calculation, whether or not the electric potential at P is zero.

[ 2 ]

[Maximum number: 1]

Electric field lines

can cross each other.

are parallel to equipotential surfaces.

are directed from negative to positive charges.

show field strength by their density.

[Maximum number: 2]

Two oppositely charged parallel plates are a distance 8.0 cm apart. The potential difference between the plates is 120 V . An alpha particle is placed on the positively charged plate and released from rest. Gravity is ignored.

(a)

Calculate the electric field between the plates.

[ 1 ]

(b)

(i)

State, in eV, the kinetic energy of the alpha particle when it arrives at the negative plate.

[ 1 ]

[Maximum number: 1]

Electrons are moving in a long wire that is normal to the plane of the paper. The electrons move into the paper.

What is the direction of the magnetic field at point P ?

[Maximum number: 1]

A sphere of mass m and positive charge q is at rest midway between two horizontal parallel plates separated by a distance s. The potential difference across the plates is V.

What is q ?

$\frac{s}{m g V}$

$\frac{V}{m g s}$

$\frac{m g V}{s}$

$\frac{m g s}{V}$

[Maximum number: 1]

Two point charges of +4 q and -q are placed a fixed distance apart. Where is the electric field strength equal to zero?

0 selected

Question 1

Question 1(c)

Question 1(c)(i)

Question 7

Question 8

Question 3

Question 3(a)

Question 3

Question 3(d)

Question 3(d)(i)

Question 3(d)(ii)

Question 14

Question 3

Question 3(a)

Question 3(b)

Question 3(b)(iii)

Question 15

Question 15

Question 15