Answer:

Explanation:
Given:
Capacitance, C = 85 pF = 85 × 10⁻¹² F
Resistance, R = 75 MΩ = 75×10⁶Ω
Charge in capacitor at any time 't' is given as:

where,
Q₀ = Maximum charge = CE
E = Initial voltage
t = time
also, Q = CV
V= Final voltage = 90% of E = 0.9E
thus, we have

or

or

taking log both sides, we get

or

or

or

Answer:
Antarctic Circle
Explanation:
The Tropic of Cancer, which is also referred to as the Northern Tropic, is the most northerly circle of latitude on Earth at which the Sun can be directly overhead. This occurs on the June solstice, when the Northern Hemisphere is tilted toward the Sun to its maximum extent.
Tropic of Capricorn Is it Southern Hemisphere counterpart, marking the most southerly position at which the Sun can be directly overhead.
Answer:
d. The large pot of water and small cup of water have the same temperature, but the large pot of water has higher thermal energy.
Explanation:
Temperature is a measure of the average kinetic energy of individual molecules. While internal energy refers to the total kinetic energy of the molecules within the object. Since in this case we have the same amount of average kinetic energy, then the large pot of water and small cup of water have the same temperature. While the large pot of water has higher thermal energy, since has more water particles than the small cup.
Answer:
a

b

Explanation:
Generally the force of attraction between this two irons is mathematically represented as
![F = \frac{k * [Q_{Li} ] * [Q_{O} ] }{ r^2}](https://tex.z-dn.net/?f=F%20%3D%20%20%5Cfrac%7Bk%20%2A%20%20%5BQ_%7BLi%7D%20%20%5D%20%2A%20%5BQ_%7BO%7D%20%20%5D%20%20%7D%7B%20r%5E2%7D)
Here k is known as the proportionality constant with value 
substituting -2 for
i.e the charge on oxygen , +1 for
i.e the charge on Lithium and
for r
So


Generally the force of repulsion will be the magnitude but different direction to the force o attraction
So Force of repulsionn is

The match
you need to light the match before you can light anything else.
and after the match is lit, maybe light the oil lamp first