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

Wavelength = speed / frequency = 340 / 17000 = 0.02 m
The answer is to this question D
Answer:
L= 12 light years
Explanation:
for length dilation we use the formula

now calculating Lo
Lo = 12.5×365×24×3600×3×10^8
= 1.183×10^17 m
now putting the values of v and Lo in the above equation we get

= 1.136×10^17 m
L=
m
so L= 12 light years
Answer:
a) The electric field at that point is
newtons per coulomb.
b) The electric force is
newtons.
Explanation:
a) Let suppose that electric field is uniform, then the following electric field can be applied:
(1)
Where:
- Electric field, measured in newtons per coulomb.
- Electric force, measured in newtons.
- Electric charge, measured in coulombs.
If we know that
and
, then the electric field at that point is:


The electric field at that point is
newtons per coulomb.
b) If we know that
and
, then the electric force is:



The electric force is
newtons.