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Height and mass of scale model
By Anonymous on Thursday, May 17, 2001 - 07:30 am:

The 300 metre tall Eiffel tower is made of steel and weighs 8 000 000 kg. An exact replica, made of the same material, weighs 1 kg. How high is the replica?

By Kerwin Hui (Kwkh2) on Friday, May 18, 2001 - 12:00 am:

The mass is proportional to the volume, which is proportional to the cube of height. So we have

Ratio of mass = (Ratio of heights)3.

Now we know the replica has only 1/8000000 the mass of the original. Hence we can work out the ratio of heights, and hence height of the replica.

Kerwin