Answer:
Centre of mass is the point at which the distribution of mass is equal in all directions, and does not depend on gravitational field. Centre of gravity is the point at which the distribution of weight is equal in all directions, and does depend on gravitational field.
Explanation:
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Answer: True
A water pump
belong to a positive displacement pump that provides constant flow of water at
fixed speed, regardless of changes in the counter pressure. The two main types
of positive displacement pump are rotary pumps and reciprocating pumps.
Moreover, water
pump is a reciprocating positive displacement pump that have an expanding
cavity on the suction side and a decreasing cavity on the discharge side. In
water pumps, the liquid flows into the pumps as the cavity on the suction side
expands and then the liquid flows out of the discharge as the cavity collapses
providing water in a pail.
Kinetic energy is the energy the makes an object move.
You would know a decomposition reaction occurred if the reactants separated. For example from AB → A+B.
Now if you look at your options only 1 works out for that equation. Letter A.
From the compound K2CO3 it split up to K2O +CO2
It cannot be letter B because synthesis/combination occurred. The same goes for letter C. Letter D, single displacement occurred.
Again, the answer is A.
Explanation:
Given that,
Wavelength of the light, 
Work function of sodium, 
The kinetic energy of the ejected electron in terms of work function is given by :

The formula of kinetic energy is given by :

Hence, this is the required solution.