Answer:
Efficiency
Explanation:
- The amount of mechanical work an engine can do per unit of heat energy it uses is called its efficiency.
- It is also defined as the output divided by the total electrical power consumed.
- In terms of heat, efficiency of engine is given by :
are output heat and input heat respectively.
Hence, the correct option is (d) "efficiency"
Answer:
Solids can hold their shape because their molecules are tightly packed together. Atoms and molecules in liquids and gases are bouncing and floating around, free to move where they want. The molecules in a solid are stuck in a specific structure or arrangement of atoms.
Answer:
Correct option is A - The force of kinetic friction is smaller than that of static friction, but Fg remains the same.
Explanation:
(A) The force of kinetic friction is smaller than that of static friction, but Fg remains the same
<h2>
Answer: 56.718 min</h2>
Explanation:
According to the Third Kepler’s Law of Planetary motion<em> </em><em>“The square of the orbital period of a planet is proportional to the cube of the semi-major axis (size) of its orbit”.
</em>
In other words, this law states a relation between the orbital period 
of a body (moon, planet, satellite) orbiting a greater body in space with the size 
of its orbit.
This Law is originally expressed as follows:
(1)
Where;
is the Gravitational Constant and its value is 
is the mass of Mars
is the semimajor axis of the orbit the spacecraft describes around Mars (assuming it is a <u>circular orbit </u>and a <u>low orbit near the surface </u>as well, the semimajor axis is equal to the radius of the orbit)
If we want to find the period, we have to express equation (1) as written below and substitute all the values:
(2)
(3)
(4)
Finally:
This is the orbital period of a spacecraft in a low orbit near the surface of mars
