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:
The intensity will be 1/9 as much.
Explanation:
The intensity of the light or any source is inversely related to the square of the distance.

Now according to the question the distance is increased by three times than,

Therefore,

Therefore the intensity will become 1/9 times to the initial intensity.
Answer: A
Explanation:
honestly, it sounded the best
Here, "Wavelength is same for both waves" it is the distance between two crests or two consecutive troughs, so, it is constant for both of them, you can easily figure it out.
In short, Your Answer would be "Wavelength"
Hope this helps!