(P4 Science: Magnets) Maglev trains are an excellent example of modern technology harnessing the forces of electromagnets. While there are some systems which levitate the train car from the track by way of repulsion thus eliminating friction, others make use of both attraction and repulsion forces to levitate and move the vehicle forward at high velocities. Reports have cited the latest prototypes travelling up to supersonic speeds of 500km/h. For some context, that's equival
[S4 / A-Level Chem] Spilling water is often a troublesome matter, but at least it's easy to clean up. The real problem comes when handling... ... a liquid that pours itself! Polyethylene oxide is a type of polymer (Topic: Macromolecules) that has very long and tangled chains, similar to bed hair. Their entanglement is so strong that it allows them to flow out of a beaker continuously, even when tipped very slightly. (As evidenced by the mess he had to clean up in the last few
We have an announcement here - our Economics tutor David Quek has published a new "A Level Economics" guidebook, which is also available at the bookstores. SIGN UP for Mr Quek's JC Economics class and we 'll give you a special discount for his book!