In my opinion, the correct answer among the choices listed above is option C. The Big Bang Theory states that between 15 and 20 billion years ago, the universe began expanding out of an enormous explosion. However, the exact number is approximately 13.8 billion years ago.
When designing the bridge model, an Engineer needs to have certain qualities like creativity, observant, ethical.. 'cause construction of bridge needs accuracy, we need extra modern design so our world can utilize it in much better way, and it's perfectness 'cause we need to secure it for much longer time
Hope this helps!
The driver speeds up with acceleration <em>a</em> so that
35 m/s = 15 m/s + <em>a</em> (10.0 s)
Solve for <em>a</em> :
20 m/s = <em>a</em> (10.0 s)
<em>a</em> = (20 m/s) / (10.0 s)
<em>a</em> = 2 m/s²
Answer: It should be A or the very left red circle that you can click on
Explanation: Because when the wind is moving downward and the earth is spinning the spot the wind ends up will never be directly down from where it was to begin with
Answer:
Part A: D
Part B: W = Qh - Qc
Part C: e = 1 - Qc/Qh
Explanation:
The heat engine is the engine that transforms heat (Q) in work (W), and by the second law of the thermodynamics, its efficiency can not be 100%, it means that some heat must be dissipated.
Part A:
The engine works with two sources of heat, one hot (Qh) at a hot temperature (Th) and another cold (Qc) at a cold temperature (Tc). It is necessary so, the hot source will give energy to the fluid of the engine, and the cold source will be the source where these heat will dissipate and the fluid will return to its original temperature. So,
Qh > Qc, and Th > Tc
Part B:
The ideal heat engine is the one that can use the most amount of heat to transform it at work. It is characterized by Qh/Qc = Th/Tc.
The work is the useful energy, so it is the total heat (Qh) less the heat dissipated (Qc):
W = Qh - Qc
Part C:
The effiency is the useful energy divided by the total energy. Because W = Qh - Qc:
e = W/Qh
e = (Qh - Qc)/Qh
e = Qh/Qh - Qc/Qh
e = 1 - Qc/Qh