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Answer: Gravitational force
Explanation:
A non contact force can be described as a force applied to an object by another body that is not in direct contact with it.
For example, an object thrown upwards will return back due to the force of gravity acting on it. So, it means Gravitational force is acting on the body without necessarily being in contact with that body.
Answer:
Velocity from second channel will be 1.6875 m/sec
Explanation:
We have given width of the channel , that is diameter of the channel 1
= 12 m
So radius 
Speed through the channel 1 
Width , that is diameter of the channel 2 
So 
From continuity equation



So velocity from smaller channel will be 1.6875 m /sec
Answer:
Hence from liquid to solid or solid to liquid the transition has to cross the grey zone. This grey zone transition is is very crucial which includes the intermolecular forces acting on the molecules and each atoms which makes the change in state from hot to cold and cold to hot.
Explanation: