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NRICH topics: Mechanics Relative velocity

Resources tagged with: Relative velocity

Content type:
Age range:
Challenge level:

There are 5 NRICH Mathematical resources connected to Relative velocity, you may find related items under Mechanics.

Broad Topics > Mechanics > Relative velocity

Problem Primary curriculum Secondary curriculum

Take a Message Soldier

A messenger runs from the rear to the head of a marching column and back. When he gets back, the rear is where the head was when he set off. What is the ratio of his speed to that of the column?

Age 14 to 18
Challenge Level Yellow starYellow star
Article Primary curriculum Secondary curriculum

Which Twin Is Older?

A simplified account of special relativity and the twins paradox.

Age 16 to 18
Problem Primary curriculum Secondary curriculum

In Constantly Passing

A car is travelling along a dual carriageway at constant speed. Every 3 minutes a bus passes going in the opposite direction, while every 6 minutes a bus passes the car travelling in the same direction. Buses leave the depot at regular intervals; they travel along the dual carriageway and back to the depot at a constant speed. At what interval do the buses leave the depot?

Age 14 to 16
Challenge Level Yellow star
Problem Primary curriculum Secondary curriculum

Escalator

At Holborn underground station there is a very long escalator. Two people are in a hurry and so climb the escalator as it is moving upwards, thus adding their speed to that of the moving steps. ... How many steps are there on the escalator?

Age 14 to 16
Challenge Level Yellow starYellow star
Problem Primary curriculum Secondary curriculum

Stonehenge

Explain why, when moving heavy objects on rollers, the object moves twice as fast as the rollers. Try a similar experiment yourself.

Age 16 to 18
Challenge Level Yellow star

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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