Physics questions and solutions

Browse original practice and official past-paper questions. Each question has its own link, with its source and worked solution.

498 questions · Page 10 of 21

1. Q3 · Original practice · 1 mark
   The graph shows the horizontal range of a projectile launched at constant speed on level ground as the launch angle changes. Which launch angle gives the greatest range?
   Projectile motion
2. Q4 · Original practice · 1 mark
   A $12.0\,\text{kg}$ block rests on a frictionless plane inclined at $23^\circ$ to the horizontal, as shown. What is the magnitude of the normal force?
   Inclined planes and circular motion
3. Q5 · Original practice · 1 mark
   A marker on a rotating platform moves in a circle of radius $0.85\,\text{m}$ with period $1.60\,\text{s}$. What is its speed?
   Inclined planes and circular motion
4. Q6 · Original practice · 1 mark
   A $0.45\,\text{kg}$ object moves at $4.2\,\text{m s}^{-1}$ in a horizontal circle of radius $0.75\,\text{m}$. What net inward force is required?
   Inclined planes and circular motion
5. Q7 · Original practice · 1 mark
   Two masses of $5.0\times10^{24}\,\text{kg}$ and $800\,\text{kg}$ are separated by $7.0\times10^6\,\text{m}$ between their centres. What is the gravitational force between them?
   Orbital mechanics
6. Q8 · Original practice · 1 mark
   The gravitational field strength at the surface of a spherical planet is $9.8\,\text{N kg}^{-1}$. At a distance of $2R$ from the planet centre, where $R$ is the planet radius, the field strength is approximately
   Orbital mechanics
7. Q9 · Original practice · 1 mark
   Satellite B orbits the same planet at four times the orbital radius of satellite A. What is $T_B/T_A$?
   Orbital mechanics
8. Q10 · Original practice · 1 mark
   A satellite is in a circular orbit of radius $8.0\times10^6\,\text{m}$ around a planet of mass $6.0\times10^{24}\,\text{kg}$. Its orbital speed is closest to
   Orbital mechanics
9. Q11 · Original practice · 1 mark
   For ideal projectile motion with negligible drag, which statement is correct?
   Projectile motion
10. Q12 · Original practice · 1 mark
    A block is sliding down a rough inclined plane. Which force acts parallel to the plane and up the slope?
    Inclined planes and circular motion
11. Q13 · Original practice · 1 mark
    For several moons orbiting the same planet, which quantity should be approximately constant?
    Orbital mechanics
12. Q14 · Original practice · 1 mark
    Two point charges $+2.0\,\mu\text{C}$ and $-3.0\,\mu\text{C}$ are separated by $0.40\,\text{m}$. What is the magnitude and nature of the electrostatic force?
    Electrostatics
13. Q15 · Original practice · 1 mark
    The diagram shows an electric field between two point charges. In which direction do the electric field lines point?
    Electrostatics
14. Q16 · Original practice · 1 mark
    A $+2.5\,\text{nC}$ charge moves through a potential difference of $+120\,\text{V}$. What is its change in electrical potential energy?
    Electrostatics
15. Q17 · Original practice · 1 mark
    A straight wire carries current out of the page, as shown. What is the direction of the magnetic field around the wire?
    Magnetic fields
16. Q18 · Original practice · 1 mark
    A long solenoid has $750$ turns per metre and carries a current of $1.8\,\text{A}$. What magnetic flux density is produced inside it?
    Magnetic fields
17. Q19 · Original practice · 1 mark
    An electron moves at $2.0\times10^6\,\text{m s}^{-1}$ perpendicular to a $0.20\,\text{T}$ magnetic field. What is the magnitude of the magnetic force?
    Magnetic fields
18. Q20 · Original practice · 1 mark
    A $0.28\,\text{m}$ wire carrying $4.0\,\text{A}$ makes an angle of $60^\circ$ with a $0.35\,\text{T}$ magnetic field. What force acts on the wire?
    Magnetic fields
19. Q21 · Original practice · 1 mark
    A uniform magnetic field of $0.50\,\text{T}$ passes through a loop of area $0.030\,\text{m}^2$. The field is at $60^\circ$ to the loop normal. What is the magnetic flux?
    Electromagnetic induction
20. Q22 · Original practice · 1 mark
    The magnetic flux through each turn of a $120$-turn coil changes by $4.0\times10^{-3}\,\text{Wb}$ in $0.080\,\text{s}$. What is the magnitude of the average induced EMF?
    Electromagnetic induction
21. Q23 · Original practice · 1 mark
    The south pole of a bar magnet approaches the left face of a conducting coil, as shown. According to Lenz’s law, the left face of the coil initially behaves as
    Electromagnetic induction
22. Q24 · Original practice · 1 mark
    An ideal transformer has $600$ primary turns and $150$ secondary turns. If the primary voltage is $240\,\text{V}$, the secondary voltage is
    Electromagnetic induction
23. Q25 · Original practice · 1 mark
    An ideal transformer supplies $3.0\,\text{A}$ at $24\,\text{V}$ from a $240\,\text{V}$ primary supply. What primary current is drawn?
    Electromagnetic induction
24. Q26 · Original practice · 1 mark
    An antenna is driven by an alternating current so that electrons oscillate back and forth. Which explanation best accounts for the radio wave emitted by the antenna?
    Electromagnetic induction