Answer:
122.84 J
Explanation:
Since plate is square, area, A is given by 
The distance between plates, d, is given in the question as 2mm=0.002m
Charge on plate, Q, as given in the question is 240 
Assuming mica dielectric constant, k of 7
Capacitance, C is given by
C=
Stored energy, E is given by
E=
Therefore, the stored energy is 122.84 J
Answer:
the force will increase by a factor 2.25
Explanation:
The gravitational force between the two stars is given by:

where
G is the gravitational constant
m1, m2 are the masses of the two stars
r is the distance between the stars
If the distance is decreased by one-third, it means that the new distance is 2/3 of the previous distance

So the new force will be

So, the force will be 2.25 times the previous value.
Answer:
During heat flow, much of the energy is dissipated and cannot be used for useful work.
Explanation:
Which of the following statements is true?
During heat flow, much of the energy is lost.
During heat flow, energy is converted to matter.
During heat flow, much of the energy is dissipated and cannot be used for useful work.
Answer:
Explanation:
Given
mass of ice 
Final temperature of liquid 
Specific heat of water 
Latent heat of fusion 
Latent heat of vaporization 
Suppose M is the mass of steam at 
Heat required to melt ice and convert it to water at 

Heat released by steam

and
must be equal as the heat gained by ice is equal to Heat released by steam


![\Rightarrow M=\dfrac{m[L+c\times T_f]}{L_v+c(100-T_f)}](https://tex.z-dn.net/?f=%5CRightarrow%20M%3D%5Cdfrac%7Bm%5BL%2Bc%5Ctimes%20T_f%5D%7D%7BL_v%2Bc%28100-T_f%29%7D)
![\Rightarrow M=\dfrac{119[333\times 10^3+4186\times 57]}{2256\times 10^3+4186\times (100-57)}](https://tex.z-dn.net/?f=%5CRightarrow%20M%3D%5Cdfrac%7B119%5B333%5Ctimes%2010%5E3%2B4186%5Ctimes%2057%5D%7D%7B2256%5Ctimes%2010%5E3%2B4186%5Ctimes%20%28100-57%29%7D)

