Answer: b
Explanation:
When heat is released by the system i.e. system loses heat. So, we take it as negative -Q
When the work is done on the system then it is considered as negative work on the system i.e. -W
In this case, the plunger is pulled out, and work is done on the system. So, we take work as negative work -W
Correct option is b
Answer:
True
Explanation:
The Sun rotates in the counterclockwise (CCW) direction when seen from its north pole. Since, the planets revolve around the Sun because of its gravity, the revolution of all the planets and their moons as seen from the north of the Sun is in CCW direction.
In fact most of the solar system bodies rotate in the same direction that is CCW. Some major exceptions to this are Venus and Uranus.
Almost all the planets and moons were made from the planetary disk around the Sun. Thus, they lie nearly in the same plane.
Crystalline solids must have a specific, orderly arrangement of atoms to be considered so.
Here light ray strikes to interface at an angle of 45 degree and then refracts into other medium such that it will bend towards boundary.
So here the angle of incidence will be less than the angle of refraction as light moves towards the boundary after refraction which mean it will bend away from the normal
here it can be said that medium 2 will be rarer then medium 1
So here the possible options are
1. Water
Air
2. Diamond
Air
So in above two options medium 1 is denser and medium 2 is rarer