Subjects · Leaving Cert Applied Maths
Leaving Cert Applied Maths: Horizontal circular motion
How often Horizontal circular motion comes up on the Applied Maths papers, every year it was asked, and questions to try.
HL Asked on 3 of the last 3 Higher Level papers, most recently in 2025. banker
OL Asked on 3 of the last 3 Ordinary Level papers, most recently in 2025. banker
Quick ones on Horizontal circular motion.
- v = ω/r
- v = rω
- v = r²ω
- Away from the centre
- Along the tangent
- Towards the centre
- 9 N
- 4.5 N
- 3 N
Show the answers
(a) v = rω
(b) Towards the centre
(c) 9 N
Higher Level
Asked on 3 of the last 3 Higher Level papers, most recently in 2025. banker
Every paper, year by year
| Year | Where it came up |
|---|---|
| 2025 | Q1 |
| 2024 | Q7 |
| 2023 | Q3 |
Links open the State Examinations Commission’s paper for that year.
More Horizontal circular motion questions
Horizontal circular motion, 3 marks
A 0.3 kg mass on a 0.5 m string moves in a circle on a smooth table at 2 m/s. Tension?
- 1.2 N
- 0.6 N
- 2.4 N
Show the answer
2.4 N
The tension is the only horizontal force, so it supplies mv²/r = 0.3 × 4 ÷ 0.5 = 2.4 N. Forgetting to square v gives 1.2 N.
Horizontal circular motion, 2 marks
Conical pendulum with string length l at angle θ to the vertical. Radius of the circle?
- r = l tan θ
- r = l sin θ
- r = l cos θ
Show the answer
r = l sin θ
The string is the hypotenuse and the radius is the side opposite θ (θ is measured from the vertical). So r = l sin θ; l cos θ is the depth below the pivot.
Horizontal circular motion, 3 marks
Conical pendulum: ω² = g/(l cos θ). What is l cos θ?
- The depth of the circle below the pivot
- The radius of the horizontal circle
- The length of the string to the bob
Show the answer
The depth of the circle below the pivot
The string of length l makes angle θ with the vertical, so its vertical drop is l cos θ. So ω depends only on how far below the pivot the circle is, not on the mass.
Ordinary Level
Asked on 3 of the last 3 Ordinary Level papers, most recently in 2025. banker
Every paper, year by year
| Year | Where it came up |
|---|---|
| 2025 | Q7 |
| 2024 | Q3 |
| 2023 | Q2 |
Links open the State Examinations Commission’s paper for that year.
More Horizontal circular motion questions
Horizontal circular motion, 3 marks
A particle moves on a circle of radius 2 m with ω = 3 rad s⁻¹. Its speed?
- 1.5 m s⁻¹
- 18 m s⁻¹
- 6 m s⁻¹
Show the answer
6 m s⁻¹
v = rω = 2 × 3 = 6 m s⁻¹. 18 is rω², which is the acceleration in m s⁻², not the speed.
Horizontal circular motion, 3 marks
A wheel turns at 2π rad s⁻¹. How many revolutions per minute is this?
- 6.28
- 60
- 120
Show the answer
60
2π rad is one revolution, so 2π rad s⁻¹ is 1 revolution per second, which is 60 per minute.
Horizontal circular motion, 2 marks
The force needed to keep a mass m moving on a circle of radius r at speed v is…
- mv² ÷ r, towards the centre
- mv² ÷ r, away from the centre
- mv ÷ r, towards the centre
Show the answer
mv² ÷ r, towards the centre
Circular motion needs a centripetal force pointing to the centre, of size mv²/r, which is the same as mrω².
Other Applied Maths topics
- Calculus & variable acceleration
- Connected particles & pulleys
- Constant acceleration (suvat)
- Dijkstra's algorithm
- Displacement & velocity graphs
- First-order difference equations
- Forces & Newton's laws
- Friction & inclined planes
- Graphs & network terminology
- Loans, savings & finance models
- Matrices & adjacency
- Minimum spanning trees
- Momentum & direct collisions
- Oblique collisions
- Projectile motion
- Recurrence relations & differences
- Reducing second-order DEs
- Resisted motion & drag
- Second-order difference equations
- Separable differential equations
- The modelling cycle & assumptions
- Vectors & the dot product
- Vertical circular motion
- Dimensional analysis
- Dynamic programming & Bellman
- Project scheduling & critical path
- Work, energy & conservation
- Greedy vs dynamic algorithms
- Hooke's law & elastic energy