It's still 20 kg. Mass doesn't change according to gravity, only weight changes.
The momentum of two or more objects during collisions is not lost nor gained
Correct answer choice is :
C) The freezing and melting temperatures of a substance are the same.
Explanation:
Fluids have a particular temperature at which they convert into solids, identified as their freezing point. In theory, the melting point of a solid should be the same as the freezing point of the liquid. In practice, small variations among these measures can be seen. The freezing point of a matter is the same as that substance's melting point. At this distinct temperature, the substance can exist as either a solid or a liquid. At temperatures below the freezing/ melting point, the substance is a solid.
Answer:
The change in gravitational potential energy of the climber-Earth system is 
Explanation:
From the question we are told that
The mass of the hiker is 
The time taken is 
The vertical elevation after time T is 
The change in gravitational potential is mathematically represented as
here g is the acceleration due to gravity with value 
substituting values
Answer:
10
Explanation:
Lets say that a,b,c,d,e are the five allowed energy states in order of decreasing energy. Then the number of possible different spectral lines comes from the electron dropping from a high state to a lower state. So, they will do so in following ways:
a - b
a - c
a - d
a- e
b - c
b - d
b- e
c - d
c- e
d- e
Ans- Ten different possible energy jumps giving six different colors or lines in the spectrum.
