Answer:
1.06 m
Explanation:
Since the charge is at the centre of two concentric spheres, we use the formula for electric potential due to a point charge. V = kq/r. Let r₁ be the radius of the sphere with potential, V₁ = 200 V and  r₂ be the radius of the sphere with potential, V₂ = 82.0 V. From V = kq/r, r = kq/V. So that r₁ = kq/V₁ and r₂ = kq/V₂. The magnitude of the difference r₁ - r₂ is the distance between the two surfaces. q the charge equals 1.63 × 10⁻⁸ C
r₂ - r₁ = kq/V₂ - kq/V₁ = kq(1/V₂ - 1/V₁) = 1.63 × 10⁻⁸ × 9 × 10⁹ (1/82 -1/200) m =  1.63 × 10⁻⁸ × 9 × 10⁹ (0.0122 - 0.005) = 1.63 × 10⁻⁸ × 9 × 10⁹(0.0072) m = 1.06 m 
The distance between them is 1.06 m
 
        
             
        
        
        
Answer:
9.75 x 10^4 J
Explanation:
Work done, W = 9.75 x 10^4 J 
According to the work energy theorem, the change in kinetic energy is equal to the work done by all the forces. 
So, here work done is 9.75 x 10^4 J so the change in kinetic energy is 9.75 x 10^4 J. 
 
        
             
        
        
        
Answer:
The value of d is 20.4 m.
(C) is correct option.
Explanation:
Given that,
Initial velocity = 20 m/s
Final velocity = 0
We need to calculate the time
Using equation of motion

Where, u = Initial velocity
v = Final velocity
Put the value into the formula


We need to calculate the distance
Using equation of motion



Hence, The value of d is 20.4 m.
 
        
             
        
        
        
This question apparently wants you to get comfortable 
with  E = m c² .  But I must say, this question is a lame 
way to do it.
c = 3 x 10⁸ m/s
                                                    E = m c²
                           1.03 x 10⁻¹³ joule  =  (m) (3 x 10⁸ m/s)²
Divide each side by (3 x 10⁸ m/s)²:
                         Mass = (1.03 x 10⁻¹³ joule) / (9 x 10¹⁶ m²/s²)
                                   =  (1.03 / 9) x (10⁻¹³ ⁻ ¹⁶) (kg)
                                   =        1.144 x 10⁻³⁰  kg .    (choice-1)
This is roughly the mass of (1 and 1/4) electrons, so it seems
that it could never happen in nature.  The question is just an
exercise in arithmetic, and not a particularly interesting one.
______________________________________
Something like this could have been much more impressive:
  
The Braidwood Nuclear Power Generating Station in northeastern
Ilinois USA serves Chicago and northern Illinois with electricity.
<span>The station has two pressurized water reactors, which can generate 
a net total of 2,242 megawatts at full capacity, making it the largest
nuclear plant in the state.
If the Braidwood plant were able to completely convert mass 
to energy, how much mass would it need to convert in order 
to provide the total electrical energy that it generates in a year, 
operating at full capacity ?
Energy = (2,242 x 10⁶ joule/sec) x (86,400 sec/day) x (365 da/yr)
             =  (2,242 x 10⁶ x 86,400 x 365) joules
             =           7.0704 x 10¹⁶ joules .
How much converted mass is that ?
                                           E  =  m c²
Divide each side by  c² :    Mass  =  E / c² .
c = 3 x 10⁸ m/s
              Mass = (7.0704 x 10¹⁶ joules) / (9 x 10¹⁶ m²/s²)
                        =        0.786 kilogram ! ! !
THAT should impress us !  If I've done the arithmetic correctly,
then roughly  (1 pound  11.7 ounces) of mass, if completely 
converted to energy, would provide all the energy generated 
by the largest nuclear power plant in Illinois, operating at max 
capacity for a year !
</span>
        
                    
             
        
        
        
g Generally the accepted value of acceleration due to gravity is 9.801 
as per the question the acceleration due to gravity is found to be 9.42 in an experiment performed.
 in an experiment performed.
the difference between the ideal and observed value is 0.381.
hence the error is -
                                                             =3.88735 percent
the error is not so high,so it can be  accepted.
now we have to know why this occurs-the equation of time period of the simple pendulum is give as-![T=2\pi\sqrt[2]{l/g}](https://tex.z-dn.net/?f=T%3D2%5Cpi%5Csqrt%5B2%5D%7Bl%2Fg%7D)
                                                       
As the experiment is done under air resistance,so it will affect to the time period.hence the time period will be more which in turn decreases the value of g.
if this experiment is done in a environment of zero air resistance,we will get the value of g which must be approximately equal to 9.801  