The height of the ball above the ground is 38.45 m
First we will calculate the velocity of the ball when it touch the ground by using first equation of motion
v=u+gt
v=0+9.81×2.8
v=27.468 m/s
now the height of the ground can be calculated by the formula
v=√2gh
27.468=√2×9.81×h
h=38.45 m
Law of reflection is the angle of incidence = angle of reflection.
Answer:
By using the Physical property we can tell the difference between matter and mass
Explanation:
Answer:
A = B = C > D
Explanation:
Work done to stop the disc is given as
so we have
(a) –2 rad/s, 5 rad/s;
(b) 2 rad/s, 5 rad/s;
(c) –2 rad/s, –5 rad/s; and
(d) 2 rad/s, –5 rad/s.
So we have
so we have
A = B = C > D
Answer:
<em>b. The current in the loop always flows in a counterclockwise direction.</em>
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Explanation:
When a magnet falls through a loop of wire, it induces an induced current on the loop of wire. This induced current is due to the motion of the magnet through the loop, which cause a change in the flux linkage of the magnet. According to Lenz law, the induced current acts in such a way as to repel the force or action that produces it. For this magnet, the only opposition possible is to stop its fall by inducing a like pole on the wire loop to repel its motion down. An induced current that flows counterclockwise in the wire loop has a polarity that is equivalent to a north pole on a magnet, and this will try to repel the motion of the magnet through the coil. Also, when the magnet goes pass the wire loop, this induced north pole will try to attract the south end of the magnet, all in a bid to stop its motion downwards.
