Heat used by electric heater :
Q = m • c • ∆T
Q = (75 kg)(4200 J/kg°C)(43°C - 15°C)
Q = 8.82 × 10⁶ J
Cost of electrical energy :
Cost = (8.82 × 10⁶ J)/(3.6 × 10⁶ J) • ($ 0.15)
Cost = $ 0.3675
<span>The moon is smaller and more dense than the Earth, and has less extreme temperature changes. The statement presented is True. In terms of temperature, since there is no atmosphere on the moon, then it has less extreme temperature changes. The moon can reach 253 Fahrenheit in the day and -387 Fahrenheit at night.</span>
Answer:
option C
Explanation:
The correct answer is option C
Fire cut of fireman cut is diagonal cut which is provided at the end of the beam to prevent the fall of masonry wall if a fire breaks out in the building.
Fire cut allows joist to leave if it fails without affecting the masonry wall standing.
Without fire cut, the burnt beam will rotate downward affecting the connection of beam and wall and leading to damage it.
Q=mcΔt
Q= 1kg * 800J/kg°C*4°C
Q= 3200J
Answer:
![\lambda = 672 nm](https://tex.z-dn.net/?f=%5Clambda%20%3D%20672%20nm)
so this is nearly red colour light
Explanation:
As we know that the interference of light from reflected light then the path difference is given as
![\Delta x = 2\mu t + \frac{\lambda}{2}](https://tex.z-dn.net/?f=%5CDelta%20x%20%3D%202%5Cmu%20t%20%2B%20%5Cfrac%7B%5Clambda%7D%7B2%7D)
now we know that for constructive interference of light the path difference is given as
![\Delta x = n\lambda](https://tex.z-dn.net/?f=%5CDelta%20x%20%3D%20n%5Clambda)
so we will have
![2\mu t + \frac{\lambda}{2} = N\lambda](https://tex.z-dn.net/?f=2%5Cmu%20t%20%2B%20%5Cfrac%7B%5Clambda%7D%7B2%7D%20%3D%20N%5Clambda)
so we will have
![4\mu t = \lambda](https://tex.z-dn.net/?f=4%5Cmu%20t%20%3D%20%5Clambda)
![\lambda = 2(1.40)(120nm)](https://tex.z-dn.net/?f=%5Clambda%20%3D%202%281.40%29%28120nm%29)
![\lambda = 672 nm](https://tex.z-dn.net/?f=%5Clambda%20%3D%20672%20nm)
so this is nearly red colour light