Answer:
The radius of the sphere is 3.6 m.
Explanation:
Given that,
Potential of first sphere = 450 V
Radial distance = 7.2 m
If the potential of sphere =150 V
We need to calculate the radius
Using formula for potential
For 450 V

....(I)
For 150 V
....(II)
Divided equation (I) by equation (II)





Hence, The radius of the sphere is 3.6 m.
Not sure... need help with it
Answer:
The value of radiation pressure is
Pa
Explanation:
Given:
Intensity

Area of piece

From the formula of radiation pressure in terms of intensity,

Where
radiation pressure,
speed of light
We know value of speed of light,

Put all values in above equation,

Pa
Therefore, the value of radiation pressure is
Pa
I think it was Isaac Newton