Scientists can show creativity by constantly coming up with new ideas and theories to test. There is always something new to think about and scientists can use their imagination in order to create something new and original that the world needs.
Answer:
(a) 43.2 kC
(b) 0.012V kWh
(c) 0.108V cents
Explanation:
<u>Given:</u>
- i = current flow = 3 A
- t = time interval for which the current flow =

- V = terminal voltage of the battery
- R = rate of energy = 9 cents/kWh
<u>Assume:</u>
- Q = charge transported as a result of charging
- E = energy expended
- C = cost of charging
Part (a):
We know that the charge flow rate is the electric current flow through a wire.

Hence, 43.2 kC of charge is transported as a result of charging.
Part (b):
We know the electrical energy dissipated due to current flow across a voltage drop for a time interval is given by:

Hence, 0.012V kWh is expended in charging the battery.
Part (c):
We know that the energy cost is equal to the product of energy expended and the rate of energy.

Hence, 0.108V cents is the charging cost of the battery.
Answer:
speed up
Explanation:
it's sound, not electromagnetic
The following expression is applicable:
Max. inductor energy = Max. capacitor energy
Where;
Max. inductor energy = LI^2/2, with L = 20.0 mH, I = 0.400 A
Max. capacitor energy = CV_max^2/2, C = 0.150 micro Faraday, V_max = Max. potential difference
Substituting;
LI^2/2 = CV^2/2
LI^2 = CV^2
V^2 = (LI^2)/C
V_max = Sqrt [(LI^2)/C] = Sqrt [(20*10^-3*0.4^2)/(0.15*10^-6)] = 146.06 V
Given:
mass = 6 kg
velocity = 4 m/s
To find:
Kinetic energy of the cart = ?
Formula used:
Kinetic energy = 
Where m = mass of the cart
v = velocity with which the cart is moving
Solution:
Kinetic energy of the moving cart is given by,
Kinetic energy = 
Where m = mass of the cart
v = velocity with which the cart is moving
Kinetic energy =
Kinetic energy = 48 Joule
Thus, the kinetic energy of the moving cart is 48 Joule.