1 ) a) increasing its thickness
2) c)potential difference
Let's say the Moon's complete cycle of phases is about 28 days (4 weeks) ... just so the arithmetic is easier. (Close enough. It's actually 29.53 days.)
If it's halfway through the waxing crescent, then it'll reach first quarter in 3 days or so.
From there, it'll take the next 7 days to become Full, and another 7 days to reach last quarter.
Total from half-waxing-crescent to last quarter . . . about 17 days.
solution:
E\delta =\frac{R}{\epsilon0}(1-\frac{A}{\sqrt{4R^{2}}-ac}
=\frac{R}{\epsilon0}(1-\frac{1}{\sqrt{4r^{2}/^{_a{2}}+1}})
=\frac{R}{\epsilon0}(1-\frac{1}{\sqrt{4x^2+1}})
x=\frac{r}{a}
infinite case,
Ei=\frac{r}{\epsilon0}
\therefore e\delta =ei(1-\frac{1}{\sqrt{4x^{2}+1}})
we have to find x when,
ei-e\delta =1% ,y=ei=1/100 ei
or,ei-ei+\frac{ei}{\sqrt{4x^2+1}} = 1/100ei
\frac{1}{\sqrt{4x^2+1}}=\frac{1}{100}
4x^2+1 =10^4
x=\frac{\sqrt{\frac{10^4-1}{4}}}=49.99\approx 50
\therefore \frac{r}{a}\approx 50
The rate of doing work is called POWER.
Power is also defined as the rate of transfer of energy. It measures the speed of how work is done.
The unit of power is WATT.
Power is computed by dividing WORK DONE by TIME TAKEN.
P = W/t
1 watt:
*power of a machine
*power of an agent that does work at the rate of 1 joule per secon
1000 watt = 1 kilowatt
1000 kilowatt = 1 megawatt
