The second law states that the total entropy can never decrese over time for an isolated system
Answer:
a)W= - 47.19 J
b)47.19 J
Explanation:
Given that
Weight ,mg= 71.5 N
y= 1.84 m
H= 2.5
a)
The distance above the hand ,h= 2.5 - 1.84 m
h= 0.66 m
We know that gravitaional force act in the downward direction but the displacement is in upward direction that is why work done will be negative.
W= - m g h
W= -71.5 x 0.66 J
W= - 47.19 J
b)
The potential energy at initial position = m g y
The potential energy at final position = m g H
So change in the potential energy = m g H - m g y
= mg ( H- y)
=71.5 ( 2.5 - 1.84 ) = 47.19 J
Therefore change in the potential energy = 47.19 J
Answer:
Explanation:
We shall apply Gauss's theorem to calculate the electric flux through a closed surface due to charge contained in side
Total charge inside surface = zero
So total electric flux through closed surface will be zero.
or electric flux going out = electric flux coming in
(a) The electric field is zero everywhere on the surface. True
(b) The electric field is normal to the surface everywhere on the surface. - false
(c) The electric flux through the surface is zero. True
(d) The electric flux through the surface could be positive or negative - false
(e) The electric flux through a portion of the surface might not be zero - True
Answer: (a) Smaller charge is and larger charge is .
(b) Smaller charge is and larger charge is .
Explanation:
(a) When both the spheres have same charge then force is repulsive in nature as like charges tend to repel each other.
Therefore, total charge on the two non-conducting spheres will be calculated as follows.
=
Therefore, force between the two spheres will be calculated as follows.
F =
12 N =
or,
This means that smaller charge is and larger charge is .
(b) When force is attractive in nature then it means both the charges are of opposite sign.
Hence, total charge on the non-conducting sphere is as follows.
Now, force between the two spheres is calculated as follows.
F =
12 N =
Hence, smaller charge is and larger charge is .
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