True.
An intrinsic semiconductor is a pure semiconductor. At room temperature it behaves as an insulator because it only has a few free and hollow electrons due to thermal energy.
In an intrinsic semiconductor there are also electron fluxes and gaps, although the total current resulting is zero. This is because the action of thermal energy produces free electrons and gaps in pairs, so there are as many free electrons as there are gaps with which the total current is zero.
Answer:
Maybe when there is a fire there can be fire drones that can take it out. and it can also resuce people who are stuck there.
Explanation:
Answer:
Explanation:
The 7 Habits of Highly Effective People, is a book written and first published in 1989. It is a business and self-help book that was written by Stephen Covey. The seven habits include
Being proactive
Starting anything with the end in mind
First things first
Always thinking towards a win-win situation
Seeking initially to understand, then going on to want to be understood
Synergize, and lastly
Growing
Answer:
The research and development plays an important role in the maintenance engineering is that it basically improve the equipment maintainability and reliability.
According to the requirement, the system and the equipment needs to be maintain in the maintenance engineering.
The research and the development basically provide the products and services and also improve the existing products and services of the system in the maintenance engineering.
Answer:
The final temperature in the vessel after the resistor has been operating for 30 min is 111.67°C
Explanation:
given information:
mass, m = 3 kg
initial temperature, T₁ = 40°C
current, I = 10 A
voltage, V = 50 V
time, t = 30 min = 1800 s
Heat for the system because of the resistance is
Q = V I t
where
V = voltage (V)
I = current (A)
t = time (s)
Q = heat transfer to the system (J)
so,
Q = V x I x t
= 50 x 10 x 1800
= 900000
= 9 x 10⁵ J
the heat transfer in the closed system is
Q = ΔU + W
where
U = internal energy
W = work done by the system
thus,
Q = ΔU + W
9 x 10⁵ = ΔU + 0, W = 0 because the tank is a well-insulated and rigid.
ΔU = 9 x 10⁵ J = 900 kJ
then, the energy change in the system is
ΔU = m c ΔT
ΔT = ΔU / m c, c = 4.186 J/g°C
= 900 / (3 x 4.186)
= 71.67°C
so,the final temperature (T₂)
ΔT = T₂ - T₁
T₂ = ΔT + T₁
= 71.67°C + 40°C
= 111.67°C
