Since sphere is performing pure rolling motion
So here the contact point of sphere with respect to inclined plane is always at rest.
This contact point will not move at any instant and and hence sphere will perform pure rolling.
So here we can say that sphere will have some friction force at the contact point but there is no displacement of that point.
So the work done by this static friction will always ZERO.


So there is no work done by friction on the sphere while it is in pure rolling.
Answer:MNO2 is a depolarizer in a dry cell
Explanation:
MNO2 is depolarizer in a dry cell. depolarizers are chemicals used to reduce or prevent polarization of cells
Answer:Electromagnetic spectrum
Explanation:
Answer:
(a) Since net charge remains same,after immersion Q is same
(b) I. 14.56pF ii. 3.05V
(c) ΔU = 5.204nJ
Explanation:
a)
C = kεA/d
k=1 for air
ε is 8.85x10-12F/m
A = .0025m2
d = .125m
C = 8.85x10-12x.0025/.125 = 1.77x10-13F = 0.177pF
Q = CV = .177pF * 244V = 43.188pC
Since net charge remains same,after immersion Q is same
b)
C = kεA/d, for distilled water k is approx. 80
Cwater = Cair x k
=0.177pF x 80 = 14.16pF
Q is same and C is changed V=Q/c holds. where Q is still 43.188pC and C is now 14.16pF, so V = 43.188pC/14.16pF = 3.05V
c) Change in energy: ΔU = Uwater - Uair
Uwater = Q2/2C = (43.188)2/2x.177pF = 5.27nJ
Uair = Q2/2C = (43.188)2/2x14.16pF = 0.066nJ
ΔU = 5.204nJ