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How does a canal lock lift a boat without lifting machinery?

A boat inside a lock rises when the water around it rises. By filling or emptying the enclosed chamber, a conventional lock brings the boat to the level of the next stretch of canal. The gates contain the water; they do not hoist the boat.

3–5 min

Questions you could explore

  • Why must the chamber and adjoining water reach compatible levels?

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Cities and transport

What happens to water before it reaches the tap?

Clear-looking water and drinking water are not necessarily the same thing. In Uisce Éireann's representative surface-water process, clarification, filtration, and disinfection deal with different parts of the treatment problem.

4–5 min

What happens to water before it reaches the tap?

Cities and transport4–5 minClear-looking water and drinking water are not necessarily the same thing. In Uisce Éireann's representative surface-water process, clarification, filtration, and disinfection deal with different parts of the treatment problem.

Cities and transport

What do the two parts of an Eircode tell you?

Ireland's seven-character address code combines a routing key with a unique identifier. The operator's public example, A65 F4E2, shows how a shared first part and an individual second part do different jobs.

2–3 min

What do the two parts of an Eircode tell you?

Cities and transport2–3 minIreland's seven-character address code combines a routing key with a unique identifier. The operator's public example, A65 F4E2, shows how a shared first part and an individual second part do different jobs.

Cities and transport

Why can irregular buses make you wait longer?

Two services can have the same average gap between buses yet create different average waits. If passengers arrive steadily without consulting a timetable, more of them arrive during long gaps than short ones. Uneven service therefore gives the longest gaps extra weight in the passenger experience.

8–10 min

Why can irregular buses make you wait longer?

Cities and transport8–10 minTwo services can have the same average gap between buses yet create different average waits. If passengers arrive steadily without consulting a timetable, more of them arrive during long gaps than short ones. Uneven service therefore gives the longest gaps extra weight in the passenger experience.

How does a canal lock lift a boat without lifting machinery? | Speech Topic | speaking.app