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Silicon melting by Czochralski Process

Why is silicon not melting?
I’m using a zvs inductive heater to try to melt some 99.85% polycrystalline silicon, as would occur in the Czochralski process,  but the silicon workpiece is not melting let alone even getting hot. The silicon workpiece is about the size of a playing dice, and becomes fully conductive after preheating to about 100* C. Even after preheating the workpiece while in the coil to achieve adequate conductivity, the inductive heater still doesn’t “take over” to raise the temperature. The inductive heater works fine with other conductive materials such as iron and aluminum and heats them quite effectively. A Czochralski process patent I came across claims that the silicon must be preheated to at least 1000* C, but many other Czochralski process
diagrams and research papers make no mention of any necessary preheating.

Asked Patrick Underwood

Relative motion in 1 dimension

A train is approaching a platform with a speed of 20 km/hr. A bird is sitting on a pole at the platform. When train is 2 km away from the pole brakes are applied so that the train accelerates uniformly, simultaneously the bird also flies towards the train with a velocity 60 km/hr. It touches the nearest point on the train and flies back and back again and so on. find total distance travelled by the bird before train stop.
Can you solve this problem by relative motion concept?

Asked Sandeep Mishra

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