Lights, signals and speed: 40 theory test questions

All 40 questions, answers and sources

1. The light turns red as you approach. There is no stop line. Where must you stop?

   1. Before the traffic light
   2. At the far side of the junction
   3. Level with the traffic light
   4. At the next pedestrian crossing
   Show the answer

   A: Before the traffic light. With no stop line, the light itself is the point you must not pass on red.

   “…beyond the stop line at that light or, if there is no stop line, you must not go beyond the light.”

2. What does a green traffic light mean?

   1. You have right of way over all traffic
   2. Go on with caution if the way is clear
   3. You must move off at once
   4. Pedestrians must wait for you
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   B: Go on with caution if the way is clear. Green allows you to proceed, but only carefully and only if the way is clear. It gives no right of way.

   “A green light is not a right of way, it is an indication that you may proceed with caution, but only if the way is clear.”

3. The light is green and you are turning left. Pedestrians are crossing the road you are entering. What should you do?

   1. Sound the horn and turn
   2. Turn, since green gives you priority
   3. Give way to the pedestrians
   4. Wait for the light to turn amber
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   C: Give way to the pedestrians. When turning on green you must take special care and give way to pedestrians who are crossing.

   “Take special care if you intend to turn left or right and give way to pedestrians who are crossing.”

4. The light changes to amber when you are very close to the stop line. When may you continue?

   1. Whenever no one is waiting to cross
   2. Only if a Garda waves you on
   3. When the car behind is close
   4. When stopping would be dangerous
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   D: When stopping would be dangerous. Amber means stop, unless you are so close when it appears that stopping would be dangerous.

   “However, you may go on if you are so close to the line or the light when the amber light first appears that stopping would be dangerous.”

5. A green arrow shows alongside a red light. What does this mean?

   1. All traffic must stop until the red light goes out
   2. The lights are out of order
   3. You may go in the arrow's direction if safe
   4. Only buses may move
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   C: You may go in the arrow's direction if safe. A green filter arrow lets you move in the direction of the arrow, if safe, even while red is showing.

   “A green arrow (also known as a filter light) means that you may move on in the direction of the arrow, assuming it is safe and the way is clear, even if a red light is also showing.”

6. You want to turn right at lights that have a right filter arrow. The main light is green. What should you do?

   1. Drive into the junction without blocking oncoming traffic
   2. Wait at the stop line until the right filter arrow appears
   3. Turn at once ahead of oncoming traffic
   4. Move to the left lane and wait
   Show the answer

   A: Drive into the junction without blocking oncoming traffic. On green you may move into the junction, keeping clear of oncoming traffic, and finish the turn when safe.

   “…drive into the junction when you see a green light. Take care not to block any oncoming traffic.”

7. A flashing amber arrow pointing left shows at a junction. What must you do?

   1. Stop and wait for a full green light before moving off
   2. Go on, as you have priority
   3. Turn left only if a bus lane is free
   4. Give way to traffic already coming through, then go
   Show the answer

   D: Give way to traffic already coming through, then go. A flashing amber arrow lets you move on, but only after giving way to traffic already passing through the junction.

   “It means that you may move on past the traffic light, but only if you first give way to traffic already coming through the junction on the other road.”

8. At a pelican crossing the amber light is flashing. What must you do?

   1. Stop and wait for green
   2. Yield to pedestrians on the crossing
   3. Drive on, as pedestrians must wait
   4. Flash your lights to warn pedestrians
   Show the answer

   B: Yield to pedestrians on the crossing. Flashing amber at a pelican crossing means pedestrians on it have priority. You may go once they have crossed.

   “Remember that a flashing amber light at a pelican crossing means you must yield to pedestrians.”

9. The traffic lights at a junction are out of order. What must you do?

   1. Stop at the control line, then go when safe
   2. Treat it as a green light and keep going at normal speed
   3. Sound your horn and drive through
   4. Follow the car in front without stopping
   Show the answer

   A: Stop at the control line, then go when safe. With broken lights you must first stop at the control line and only go when safe, yielding to traffic with right of way.

   “If the traffic lights at a controlled junction are out of order, you must first stop at the control line and only proceed when it is safe to do so…”

10. Which of these does the law require you to signal before doing?

    1. Driving straight through a junction
    2. Slowing down
    3. Following the road around a bend
    4. Checking your mirrors
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    B: Slowing down. The law lists slowing down, along with moving off, turning, changing lanes, overtaking and stopping, as needing a signal.

    “The law requires you to signal properly before moving off, turning right or left, changing lanes, overtaking, slowing down or stopping.”

11. You have indicated to change lanes. What does your signal give you?

    1. Right of way over the other lane
    2. Priority once it has flashed three times
    3. Nothing beyond showing your intention
    4. The right to move after five seconds
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    C: Nothing beyond showing your intention. A signal only shows what you plan to do. It never gives you right of way.

    “Signals are an indication of intent – they do not confer a right of way.”

12. You think your brake lights may not be giving a clear signal. What should you do?

    1. Brake harder so others notice
    2. Switch on your hazard lights
    3. Flash your headlights instead
    4. Use clear hand signals as well
    Show the answer

    D: Use clear hand signals as well. If indicators or stop lamps may not be clear, back them up with decisive hand signals.

    “If you are concerned that, for whatever reason, your direction indicators or stop lamps are not giving an adequate signal, use clear, decisive hand signals as well.”

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13. You believe your indicators have stopped working. What should you do?

    1. Carry on as normal
    2. Use only your horn
    3. Use hand signals and get them repaired
    4. Drive with hazard lights on
    Show the answer

    C: Use hand signals and get them repaired. Hand signals help in the meantime, but faulty indicators should be repaired before you continue your journey.

    “…where you believe your indicators are not working (you should have them repaired before continuing your journey).”

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14. A driver ahead moves their arm out of the window in an anti-clockwise circle. What does this mean?

    1. They are going to turn left
    2. They are going to slow down
    3. They want you to overtake
    4. They are going to turn right
    Show the answer

    A: They are going to turn left. The anti-clockwise arm movement is the car driver's signal to traffic behind for turning left.

    “I am going to turn to my left. Note that the car driver moves his arm and hand in an anti-clockwise direction.”

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15. How does a car driver show a pointsman that they want to turn left?

    1. Right arm straight out, palm down
    2. Right arm moved slowly up and down out of the window
    3. Left hand raised above the roof
    4. Right forearm and hand, fingers pointing left
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    D: Right forearm and hand, fingers pointing left. To a pointsman, the car driver points the right forearm and hand with fingers extended to the left.

    “Note that the car driver points the right forearm and hand with the fingers extended to the left.”

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16. What is the basic legal rule on the speed you choose?

    1. You may always drive at the posted limit, whatever the conditions
    2. You must be able to stop within the distance you see clear
    3. You must never drop below 50 km/h
    4. You must match the car in front
    Show the answer

    B: You must be able to stop within the distance you see clear. Whatever the limit, your speed must let you stop within the distance you can see to be clear.

    “A vehicle must not be driven at a speed exceeding that which will enable its driver to bring it to a halt within a distance the driver can see to be clear.”

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17. Do speed limits apply to cyclists and e-scooter users?

    1. Yes, they apply to all road users
    2. No, only to motor vehicles
    3. Only on national roads
    4. Only to e-scooters, not bicycles
    Show the answer

    A: Yes, they apply to all road users. Speed limits apply to everyone on the road, including bicycles, e-bikes and e-scooters.

    “Speed limits apply to all road users. This includes bicycles, e-bikes, e-scooters, e-mopeds, motorbikes and other motor vehicles.”

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18. When judging your speed, which of these counts as a possible hazard?

    1. A clear road with good visibility
    2. Being stressed or tired yourself
    3. The colour of your car
    4. The radio being switched off
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    B: Being stressed or tired yourself. Possible hazards include your own physical and mental state, such as stress or tiredness.

    “It includes your own physical and mental state while driving (for example whether you are stressed or tired) and the condition of your vehicle.”

19. On a dry road, what is the minimum gap to keep behind the vehicle in front?

    1. One second
    2. One car length
    3. Two seconds
    4. Five metres
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    C: Two seconds. The two-second rule sets the safe headway in dry conditions.

    “Keep a safe headway by ensuring you are at least two seconds behind the vehicle in front.”

20. It is raining. How should you change your following distance?

    1. Keep it the same
    2. Add one car length
    3. Halve it, as speeds are lower
    4. Double it
    Show the answer

    D: Double it. In wet weather you should double the gap, saying the two-second phrase twice.

    “In wet weather, double the distance between your vehicle and the one in front of you…”

21. In snow, fog or ice, how many times may you need to repeat the two-second phrase?

    1. Twice
    2. 3 times
    3. 4 or 5 times
    4. Once, but slowly
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    C: 4 or 5 times. Severe conditions can call for a gap of four or five times the dry-road gap.

    “If travelling in more severe conditions such as snow, fog and ice, you may need to repeat 'only a fool breaks the two-second rule' 4 or 5 times.”

22. When should you avoid using cruise control?

    1. In heavy rain, snow, fog or ice
    2. On motorways in light traffic
    3. On long straight roads
    4. When the road is dry
    Show the answer

    A: In heavy rain, snow, fog or ice. Cruise control can reduce your control and slow your reaction in poor conditions.

    “Avoid using cruise control in heavy rain, hail, snow, fog and icy conditions.”

23. Why can driving too slowly in normal conditions be dangerous?

    1. It wears out the clutch and brakes much faster
    2. It is always illegal
    3. It makes your lights dimmer
    4. It may lead others to overtake dangerously
    Show the answer

    D: It may lead others to overtake dangerously. Holding up traffic without need can frustrate drivers and lead to risky overtaking.

    “If you drive too slowly, you risk frustrating other drivers, which could lead to dangerous overtaking.”

24. What does a speed limit sign tell you?

    1. The speed you must drive at
    2. The maximum legal speed, not a target
    3. The minimum speed for the road
    4. The average speed of traffic
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    B: The maximum legal speed, not a target. A speed limit is the most you may do, not a required speed.

    “The signs indicate the maximum speed at which your vehicle may travel on a particular road or stretch of road, not the required speed for the road.”

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25. There is no speed limit sign on a road. Which limit applies?

    1. The default limit for that type of road
    2. No limit applies
    3. Always 50 km/h, wherever the road is
    4. The limit of the last road you were on
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    A: The default limit for that type of road. A default limit applies automatically to each type of road unless a sign says otherwise.

    “This automatically applies to a particular type of road if there is no speed limit sign to show otherwise.”

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26. You are tailgating and run into the car in front when it brakes suddenly. Who is liable?

    1. The driver in front
    2. You are
    3. Both drivers equally
    4. No one, if it was sudden
    Show the answer

    B: You are. Driving too close leaves no time to react, and the following driver is liable for the damage.

    “If you run into the vehicle, you will be liable for any damage caused.”

27. What is the default speed limit on a national primary road (green signs, N numbers)?

    1. 80 km/h
    2. 120 km/h
    3. 100 km/h
    4. 60 km/h
    Show the answer

    C: 100 km/h. National roads have a default limit of 100 km/h. A cut to 80 km/h on national secondary roads is planned, so always follow the signs.

    “National roads (primary and secondary) (Green Signs - N numbers) 100kmh Regional roads 80kmh…”

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28. What is the default speed limit on a regional road?

    1. 60 km/h
    2. 100 km/h
    3. 50 km/h
    4. 80 km/h
    Show the answer

    D: 80 km/h. Regional roads have a default limit of 80 km/h.

    “100kmh Regional roads 80kmh Local roads 60kmh…”

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29. What is the default speed limit on a local road?

    1. 80 km/h
    2. 50 km/h
    3. 60 km/h
    4. 40 km/h
    Show the answer

    C: 60 km/h. Local roads have a default limit of 60 km/h.

    “Regional roads 80kmh Local roads 60kmh Roads in built-up areas, such as cities, towns and boroughs…”

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30. What is the default speed limit on roads in a town or city?

    1. 50 km/h
    2. 60 km/h
    3. 30 km/h
    4. 40 km/h
    Show the answer

    A: 50 km/h. Roads in built-up areas such as cities, towns and boroughs have a default limit of 50 km/h. Many urban streets now have a lower 30 km/h limit, so watch the signs.

    “Roads in built-up areas, such as cities, towns and boroughs 50kmh Special speed limits…”

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31. Which vehicles may exceed the road speed limit?

    1. Doctors on call in their own cars
    2. Taxis carrying passengers to a hospital
    3. Any car overtaking a slow vehicle
    4. Fire engines, ambulances and Garda vehicles
    Show the answer

    D: Fire engines, ambulances and Garda vehicles. Only fire engines, ambulances and Garda vehicles may go above the road speed limit.

    “No vehicle other than fire engines, ambulances or Garda vehicles may exceed the road speed limit at any time.”

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32. You pass a school periodic speed limit sign outside the times it applies. Which limit is in force?

    1. The periodic limit at all times
    2. The usual limit at that location
    3. 30 km/h until the next sign
    4. No limit applies
    Show the answer

    B: The usual limit at that location. Outside the set times or days, the normal speed limit for that location applies.

    “Outside these times or days, the usual speed limit at that location is in force.”

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33. Is it legal to carry a device that detects speed cameras?

    1. No, it is against the law
    2. Yes, if it is switched off
    3. Yes, outside built-up areas
    4. Only for commercial drivers
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    A: No, it is against the law. Supplying, carrying or using a device that detects or interferes with speed checks is illegal.

    “It is against the law to supply, carry or use any device that can detect or interfere with any speed monitoring equipment…”

34. You are towing a caravan. What is the highest speed you may drive, even where the road limit is higher?

    1. 100 km/h
    2. 80 km/h
    3. 90 km/h
    4. 120 km/h on motorways
    Show the answer

    B: 80 km/h. Any vehicle towing a trailer, caravan or horsebox is limited to 80 km/h, and to the road limit where that is lower.

    “80 kilometres an hour (80kmh) On all roads Any vehicle towing a trailer, caravan, horsebox or other attachment…”

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35. Your vehicle limit and the road limit are different. Which must you obey?

    1. The higher of the two
    2. The road limit only
    3. The lower of the two
    4. The vehicle limit only
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    C: The lower of the two. When the two limits differ, the lower one always applies.

    “If the vehicle and road speeds are different, the driver must obey the lower of the two.”

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36. What is meant by perception time?

    1. Time to move your foot from the accelerator to the brake
    2. Time for the brakes to stop the car
    3. Time for the car ahead to stop
    4. Time to see a hazard and realise you must act
    Show the answer

    D: Time to see a hazard and realise you must act. Perception time covers spotting a hazard and recognising it needs immediate action.

    “Your perception time is how long it takes you to see a hazard and for your brain to realise it is a hazard requiring you to take immediate action.”

37. Which of these can lengthen your perception and reaction time?

    1. Good tyre tread
    2. Driving in daylight
    3. Tiredness
    4. A fully serviced car
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    C: Tiredness. Alcohol, drugs, tiredness, fatigue and poor concentration all slow the parts of stopping that depend on you.

    “These first two components of stopping distance are down to you, and they can be affected by alcohol, drugs, tiredness, fatigue or lack of concentration.”

38. If you double your speed, roughly what happens to your braking distance?

    1. It becomes nearly four times as long
    2. It doubles, in line with the speed
    3. It stays about the same
    4. It becomes three times as long
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    A: It becomes nearly four times as long. Braking distance grows much faster than speed. Doubling speed multiplies it nearly four times.

    “When you double the speed of your car, you multiply the total braking distance nearly four times.”

39. A pedestrian is hit by a car at 50 km/h. How many out of 10 are likely to be killed?

    1. 1 out of 10
    2. 9 out of 10
    3. 3 out of 10
    4. 5 out of 10
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    D: 5 out of 10. At 50 km/h about half of pedestrians hit are killed, showing how much small speed changes matter.

    “Hit by a car at 50kmh, 5 out of 10 of pedestrians will be killed.”

40. What is aquaplaning?

    1. Skidding on black ice
    2. A film of water builds up between tyres and road
    3. Brakes overheating and fading after long use in heavy rain
    4. Water entering the engine
    Show the answer

    B: A film of water builds up between tyres and road. On a wet road, water can build up under the tyres so the car loses contact, affecting braking and steering.

    “'Aquaplaning' occurs when a car is being driven on a wet road and a film of water builds up between the tyres and the road surface.”