Force = mass times acceleration
F = 21000 x 36.9 = 774900
Therefore, 774900N force is required.
The current that flows in the circuit is
(voltage applied to the circuit)
divided by
(net resistance of the circuit) .
The resistance of most circuits is constant. So this simple formula
shows that the current is directly proportional to the applied voltage.
If the applied voltage increases, so does the current.
There are no questions on the list you've provided
that <span>would be answered using concepts from physics.
</span>
(1).....opaque -object that not allow light to pass through it
we can't look through opaque objects
ex..wall
translucent... objects that all some light to pass through it
we can partially see through it
ex...coloured glass window
transparent... objects that wholly allow light to pass through it
we can clearly see through it
ex...glass of specs
(2)..the bouncing back of light from a smooth polished surface is called reflection of light
(3)/.....there must be a solid ,opaque to block light
there must be a source of light
there must be a surface to have shadow on it..
(6)...reflected images r formed by light reflection from a smooth polished surface while shadows are formed by blockage of light by an solid,opaque object...