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The animation shows the way forces act on wheeled vehicles and vehicles with runners.
In rock-paper-scissors, the least popular choice of players is paper. But is it really the...
A force can be measured by measuring the twisting of the torsion wire in a torsion balance.
The length of the metal frameworks of bridges change when the temperature changes.
The three important laws describing planetary motion were formulated by Johannes Kepler.
Can a candle be re-lit if the flame of the match does not even touch it?
Direct action pumps and suction pumps are among the simplest water pumps.
A spectacular optical illusion using a chain of closed rings.