Answer:
I = Δq / t
Explanation:
The quantity of electricity i.e charge is related to current and time according to the equation equation:
Q = It
Δq = It
Where:
Q => is the quantity of electricity i.e charge
I => is the current.
t => is the time.
Thus, we can rearrange the above expression to make 'I' the subject. This is illustrated below:
Δq = It
Divide both side by t
I = Δq / t
Answer:
The compression in the spring is 5.88 meters.
Explanation:
Given that,
Mass of the car, m = 39000 kg
Height of the car, h = 19 m
Spring constant of the spring, 
We need to find the compression in the spring in stopping the ore car. It can be done by balancing loss in gravitational potential energy and the increase in elastic energy. So,

x is the compression in spring

So, the compression in the spring is 5.88 meters.
Answer:
The charge resides on the outer surface =
C
Explanation:
Surface area of cell 
Separation between two plate
Dielectric constant 
Potential difference 
The capacitance of parallel plate capacitor in free space is given by,

Where
permittivity of free space = 
The Capacitance of capacitor is increase by
times when it placed in dielectric medium.

And we know that, 
So charge on the outer surface is given by,



Answer:
7.5 km/h (2.1 m/s) due east
Explanation:
The average velocity of the person is given by:

where
d is the displacement
t is the time taken
In this problem,
d = 15 km is the displacement
t = 2.0 h is the time elapsed
so the average velocity is

and the direction is the same as the displacement (east).
We can also convert the velocity into SI units (m/s). We have:
d = 15 km = 15,000 m
t = 2.0 h * 3600 s/h = 7200 s
