Answer:
A bug must swim as fast as the wave speed to keep up with the waves it produces. Moreso, a boat must be moving faster than the waves it creates to produce a bow wave.
So basically the objects would be sandpaper and smooth metal, the sandpaper can indirectly touch the metal since it’s so smooth and it won’t cause any temp change either
<span>Volume of air in the balloon 1.01 x 10^6 L
Density of air is 1.20 g/l
Mass = Density X Volume
So mass of the air in the Balloon= ( 1.01 x 10^6) X 1.20 = 1.212 x 10^6 g
As the air is heated, the volume of air in the balloon expands to 1.10x 10^6 L
Density= Mass/ voume
So the Density of heated air = 1.212 x 10^6/ 1.10x 10^6 = 1.101 g/l
The answer is 1.101 g/l.</span>
Recall that

where
and
are the initial and final velocities, respecitvely;
is the acceleration; and
is the change in position.
So we have


(Normally, this equation has two solutions, but we omit the negative one because the car is moving in one direction.)
Current is created when charges are quickened by an electric field to move where the position of lower temperature. An electric current is a stream of electric charge. In electric circuits, this charge is regularly conveyed by moving electrons in a wire.