Answer:
![T_b=107.3784\ ^{\circ}C](https://tex.z-dn.net/?f=T_b%3D107.3784%5C%20%5E%7B%5Ccirc%7DC)
Explanation:
Given:
- thickness of the base of the kettle,
![dx=0.52\ cm=5.2\times 10^{-3}\ m](https://tex.z-dn.net/?f=dx%3D0.52%5C%20cm%3D5.2%5Ctimes%2010%5E%7B-3%7D%5C%20m)
- radius of the base of the kettle,
![r=0.12\ m](https://tex.z-dn.net/?f=r%3D0.12%5C%20m)
- temperature of the top surface of the kettle base,
![T_t=100^{\circ}C](https://tex.z-dn.net/?f=T_t%3D100%5E%7B%5Ccirc%7DC)
- rate of heat transfer through the kettle to boil water,
![\dot Q=0.409\ kg.min^{-1}](https://tex.z-dn.net/?f=%5Cdot%20Q%3D0.409%5C%20kg.min%5E%7B-1%7D)
- We have the latent heat vaporization of water,
![L=2260\times 10^3\ J.kg^{-1}](https://tex.z-dn.net/?f=L%3D2260%5Ctimes%2010%5E3%5C%20J.kg%5E%7B-1%7D)
- and thermal conductivity of aluminium,
![k=240\ W.m^{-1}.K^{-1}](https://tex.z-dn.net/?f=k%3D240%5C%20W.m%5E%7B-1%7D.K%5E%7B-1%7D)
<u>So, the heat rate:</u>
![\dot Q=\frac{0.409\times 2260000}{60}](https://tex.z-dn.net/?f=%5Cdot%20Q%3D%5Cfrac%7B0.409%5Ctimes%202260000%7D%7B60%7D)
![\dot Q=15405.67\ W](https://tex.z-dn.net/?f=%5Cdot%20Q%3D15405.67%5C%20W)
<u>From the Fourier's law of conduction we have:</u>
![\dot Q=k.A.\frac{dT}{dx}](https://tex.z-dn.net/?f=%5Cdot%20Q%3Dk.A.%5Cfrac%7BdT%7D%7Bdx%7D)
![\dot Q=k\times \pi.r^2\times \frac{T_b-T_t}{5.2\times 10^{-3}}](https://tex.z-dn.net/?f=%5Cdot%20Q%3Dk%5Ctimes%20%5Cpi.r%5E2%5Ctimes%20%5Cfrac%7BT_b-T_t%7D%7B5.2%5Ctimes%2010%5E%7B-3%7D%7D)
where:
area of the surface through which conduction occurs
temperature of the bottom surface
![15405.67=240\times \pi\times 0.12^2\times \frac{T_b-100}{5.2\times 10^{-3}}](https://tex.z-dn.net/?f=15405.67%3D240%5Ctimes%20%5Cpi%5Ctimes%200.12%5E2%5Ctimes%20%5Cfrac%7BT_b-100%7D%7B5.2%5Ctimes%2010%5E%7B-3%7D%7D)
is the temperature of the bottom of the base surface of the kettle.
Answer:
just calmly talk and get money to pay them the bike and explain it to them
Explanation:
Answer: An object at rest has zero velocity - and (in the absence of an unbalanced force) will remain with a zero velocity. Such an object will not change its state of motion.
Explanation: I hoped that helped!!
Answer:
(A). The flux is 0.336 N.m²/C
(B). The flux is zero.
Explanation:
Given that,
Length = 4.2 cm
Width = 4.0 cm
Electric field ![E=(150 i-200 k)\ N/C](https://tex.z-dn.net/?f=E%3D%28150%20i-200%20k%29%5C%20N%2FC)
Area vector is perpendicular to xy plane
(A). We need to calculate the flux
Using formula of flux
![\phi=E\cdot A](https://tex.z-dn.net/?f=%5Cphi%3DE%5Ccdot%20A)
Where, E = electric field
A = area
Put the value into the formula
![\phi=(150 i-200 k)\times(4.2\times10^{-2}\times4.0\times10^{-2})k](https://tex.z-dn.net/?f=%5Cphi%3D%28150%20i-200%20k%29%5Ctimes%284.2%5Ctimes10%5E%7B-2%7D%5Ctimes4.0%5Ctimes10%5E%7B-2%7D%29k)
![\phi=-200\times4.2\times10^{-2}\times4.0\times10^{-2}](https://tex.z-dn.net/?f=%5Cphi%3D-200%5Ctimes4.2%5Ctimes10%5E%7B-2%7D%5Ctimes4.0%5Ctimes10%5E%7B-2%7D)
![\phi=-0.336\ N.m^2/C](https://tex.z-dn.net/?f=%5Cphi%3D-0.336%5C%20N.m%5E2%2FC)
(B). Given electric field
![E=(150i-200j)\ N/C](https://tex.z-dn.net/?f=E%3D%28150i-200j%29%5C%20N%2FC)
We need to calculate the flux
Using formula of flux
![\phi=E\cdot A](https://tex.z-dn.net/?f=%5Cphi%3DE%5Ccdot%20A)
Put the value into the formula
![\phi=(150 i-200 j)\times(4.2\times10^{-2}\times4.0\times10^{-2})k](https://tex.z-dn.net/?f=%5Cphi%3D%28150%20i-200%20j%29%5Ctimes%284.2%5Ctimes10%5E%7B-2%7D%5Ctimes4.0%5Ctimes10%5E%7B-2%7D%29k)
Here, The component of k is not given
So, the flux is
![\phi=0](https://tex.z-dn.net/?f=%5Cphi%3D0)
Hence, (A). The flux is -0.336 N.m²/C
(B). The flux is zero.
Answer:
A real emf device has an internal resistance, but an ideal emf device does not.