Answer:
surface temperature = 128.74⁰c
Explanation:
Given data
diameter of cable = 5 mm = 0.005 m
length of cable = 4 m
T∞ ( surrounding temperature ) = 20⁰c
voltage drop across cable ( dv )= 60 V
current across cable = 1.5 A
attached to this answer is the comprehensive analysis and solution to the problem.
The assumption made is not a good one since the calculated Ts ( surface temperature ) is very much different from the assumed Ts
Answer:
Correct option: B. 90%
Explanation:
The confidence interval is given by:
![CI = [\bar{x} - z\sigma_{\bar{x}} , \bar{x}+z\sigma_{\bar{x}} ]](https://tex.z-dn.net/?f=CI%20%3D%20%5B%5Cbar%7Bx%7D%20-%20z%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%2C%20%5Cbar%7Bx%7D%2Bz%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%5D)
If
is 190, we can find the value of
:
![\bar{x} - z\sigma_{\bar{x}} = 188.29](https://tex.z-dn.net/?f=%5Cbar%7Bx%7D%20-%20z%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%20%3D%20188.29)
![190 - z\sigma_{\bar{x}} = 188.29](https://tex.z-dn.net/?f=190%20-%20z%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%20%3D%20188.29)
![z\sigma_{\bar{x}} = 1.71](https://tex.z-dn.net/?f=z%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%20%3D%201.71)
Now we need to find the value of
:
![\sigma_{\bar{x}} = 5/ \sqrt{25}](https://tex.z-dn.net/?f=%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%3D%205%2F%20%5Csqrt%7B25%7D)
![\sigma_{\bar{x}} = 1](https://tex.z-dn.net/?f=%5Csigma_%7B%5Cbar%7Bx%7D%7D%20%3D%201)
So the value of z is 1.71.
Looking at the z-table, the z value that gives a z-score of 1.71 is 0.0436
This value will occur in both sides of the normal curve, so the confidence level is:
![CI = 1 - 2*0.0436 = 0.9128 = 91.28\%](https://tex.z-dn.net/?f=CI%20%3D%201%20-%202%2A0.0436%20%3D%200.9128%20%3D%2091.28%5C%25)
The nearest CI in the options is 90%, so the correct option is B.
Answer:
B
Explanation:
it's does not transmit any energy
emf generated by the coil is 1.57 V
Explanation:
Given details-
Number of turns of wire- 1000 turns
The diameter of the wire coil- 1 cm
Magnetic field (Initial)= 0.10 T
Magnetic Field (Final)=0.30 T
Time=10 ms
The orientation of the axis of the coil= parallel to the field.
We know that EMF of the coil is mathematically represented as –
E=N(ΔФ/Δt)
Where E= emf generated
ΔФ= change inmagnetic flux
Δt= change in time
N= no of turns*area of the coil
Substituting the values of the above variables
=1000*3.14*0.5*10-4
=.0785
E=0.0785(.2/10*10-3)
=1.57 V
Thus, the emf generated is 1.57 V
Answer:
The invention of the pendulum-driven ___<u>clocks</u>___ in the 1600s paved the way for a new industrial era.