Water boils at 100°C at normal pressure of 1 arm or 100000 Pascal. Boiling temperature increases with the increase in pressure above the liquid surface. When we cook food in pressure cooker, the pressure increases due the retention of vapour and hence the boiling temperature increases in the pressure cooker upto 125°C As food is cooked at higher temperature than 100°C , it is cooked faster in the pressure cooker.
In uniform circular motion, 1. Speed is constant. 2. Velocity is variable and acts along tangential direction at a point. 3. Centripetal Force and acceleration act along the radius towards the centre if the circular path. 4. Centrifugal force appears to act radially outwards. It is a virtual ,fictitious force, not a real force.
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