Answer:
C. Low viscosity for Maine in the winter and high viscosity for Florida in the summer.
Explanation:
The choice of motor oil or engine oil depends on the type of engine and also on the type of climate on which the engine runs.
In winter climates, we should use oil with low viscosity as at lower temperatures, the it flows more readily if its viscosity is low.
But the summer season needs a relatively thicker oil so as to reduce the thinning effect of the oil out of the engine.
Thus for Maine in the winter season, we need a low viscosity oil and for Florida a high viscosity oil in the summer season.
Therefore, option (c) is correct.
Answer:
B) a kinetic friction
Explanation:
The force of friction in a movement object its called kinetic friction force (<em>fk). </em>The net force acting in the direction of the movement its express, according to the Newton second law, like this: F- <em>fk. </em>That expression says that the net force produces an aceleration in the direction of the movement of the object.
Now if the force its removed, the <em>fk</em> its continue acting in the object but now in the opposite direction. And according to the Newton second law this <em>fk </em>it going to continue acting until the object stay in a still state.
<u>In conclusion</u>, if an object moves in some direction the kinetic friction force always be opposite to that direction of movement, according to the Newton second law
Answer:
(b)False
Explanation:
We know that specific Internal energy of gas u=
T
and specific enthalpy of gas h=
T
If we take the case of air we know that
=0.707 KJ/Kg=K , =1.005 KJ/Kg=K
If we take A fixed temperature T=300 K
so u=212.1 KJ/ kg ,h=301.5 KJ/kg
So we can say that specific enthaply of gas is always greater than its specific internal energy.
