Well, first of all, EVERY physical quantity is measured in a combination
of 2 or more units, except for mass, length, time, and electric charge.
ALL other units are made out of these. So it should not surprise you.
[ Example: Speed = (length) / (time) ]
Density is not the mass of a substance. It's the mass of a substance in
a standard volume of it. So the density is made of the mass in any lump
and the volume of that lump. That way, no matter how much of a substance
you have, you can always compare the lump you have to all other substances.
In a series circuit, a common current flows through all the components of the circuit. While in a parallel circuit, a different amount of current flows through each parallel branch of the circuit. Whereas in the parallel circuit, the same voltage exists across the multiple components in the circuit.
Hope It Helps!
When we hit the puck from tap the puck will move forward.
This is due to the impulse provided by us at the time of hit. Due to this impulse the puck will move forward and start moving in some direction.
As soon as puck move forward the force on it is zero as the weight of the puck is counterbalanced by the air stream force and there is no other force on it so puck will continue its motion till it will hit at some other point.
So here the motion of the puck will be uniform motion till it will collide with some other points.
So here the correct option will be given as
<em>moves with a constant speed until hitting the other end.</em>
