Answer: a) 73.41 10^-12 F; b)4.83* 10^3 N/C; c) 3.66 *10^3 N/C
Explanation: To solve this problem we have to consider the following: The Capacity= Charge/Potential Difference
As we know the capacity is value that depend on the geometry of the capacitor, in our case two concentric spheres.
So Potential Difference between the spheres is given by:
ΔV=-
Where E = k*Q/ r^2
so we have 
then
Vb-Va=k*Q(1/b-1/a)=kQ (ab/b-a)
Finally using C=Q/ΔV=ab/(k(b-a))
To caclulate the electric firld we first obtain the charge
Q=ΔV*C=120 V*73.41 10^-12 F=8.8 10^-9 C
so E=KQ/r^2 for both values of r
r=12.8 cm ( in meters)
r2=14.7 cm
E(r1)=4.83* 10^3 N/C
E(r2)=3.66 *10^3 N/C
Answer:
0.82 m
Explanation:
The ball is in free fall - uniform accelerated motion with constant acceleration downward,
(acceleration of gravity). So we can use the following suvat equation to solve the problem:

where
v is the final velocity
u = 4 m/s is the initial velocity
a is the acceleration
s is the displacement
At the maximum displacement, v = 0 (the velocity becomes zero). Substituting and solving for s, we find:

Answer:
Explanation:
Given
mass of person is m
Distance between bridge and river is h
chord has an un-stretched length of 
Let spring constant be k
Person will just stop before hitting the river
Conserve energy i.e. Potential Energy of Person is converted in to elastic energy of chord




Thus 
Answer:
Impedance, Z = 107 ohms
Explanation:
It is given that,
Resistance, R = 100 ohms
Inductance, 
Capacitance, 
Frequency, f = 60 Hz
Voltage, V = 120 V
The impedance of the circuit is given by :
...........(1)
Where
is the capacitive reactance, 

is the inductive reactance, 

So, equation (1) becomes :

Z = 106.26 ohms
or
Z = 107 ohms
So, the impedance of the circuit is 107 ohms. Hence, this is the required solution.
Fulcrum need to be positioned balanced with weight on both the sides following law of lever.
What is the physical law of the lever?
- It is the foundation for issues with weight and balance. According to this rule, a lever is balanced when the weight multiplied by the arm on one side of the fulcrum, which serves as the pivot point for the device, equals the weight multiplied by the arm on the opposing side.
- The lever is balanced, in other words, when the sum of the moments about the fulcrum is zero.
- The situation in which the positive moments (those attempting to turn the lever clockwise) equal the negative moments is known as this (those that try to rotate it counterclockwise).
- Moving the weights closer to or away from the fulcrum, as well as raising or lowering the weights, can alter the balance point, or CG, of the lever.
Learn more about the Fulcrum with the help of the given link:
brainly.com/question/16422662
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