Answer:
The time constant is 
Explanation:
From the question we are told that
the time take to charge is 
The mathematically representation for voltage potential of a capacitor at different time is

Where
is the time constant
is the potential of the capacitor when it is full
So the capacitor potential will be 100% when it is full thus
100% = 1
and from the question we are told that the at the given time the potential of the capacitor is 85% = 0.85 of its final potential so
V = 0.85
Hence



Close the switch would be the correct answer
Answer:
If the final question is; at what velocity will the first block start to move outward in m/s?

Explanation:
The motion have the velocity that will make the block move using:




μ
Resolving:





Answer:

Explanation:
Given that
Speed ,v= 2 x 10⁵ m/s ( - y direction)
B= 0.6 T (- z direction)
The resultant force on the proton given as

F= m a
For uniform motion acceleration should be zero.
F = 0






Electric filed should be apply in the negative x direction.
Here is a helpful video https://www.khanacademy.org/_render