Answer:
Wave A.
Explanation:
The energy of a wave is directly proportional to the square of the amplitude.
If a wave has higher amplitude, it will have more energy. On the other hand, a wave having lower amplitude, it will have less eenergy.
In this case, we need to tell which wave has higher energy. Hence, the correct option is A because it has a higher amplitude.
Answer:
When her hands extends, her momen of inertia is
.
Explanation:
Given that,
Initial angular speed, 
Initial moment of inertia, 
Final angular speed, 
Initially, a skater rotates with her arms crossed and finally she extends her arms. The momentum remains conserved. Using the conservation of momentum as :

is final moment of inertia

So, when her hands extends, her momen of inertia is
. Hence, this is the required solution.
Answer:
Melt.
Explanation:
When rocks melt, they do so slowly and gradually because most rocks are made of several minerals, which all have different melting points; moreover, the physical and chemical relationships controlling the melting are complex. As a rock melts, for example, its volume changes. When enough rock is melted, the small globules of melt link up and soften the rock.
Under normal conditions, mantle rock like peridotite shouldn't melt in the Earth's upper mantle. However, by adding water you can lower the melting point of the rock. Alternatively, by decompressing the rock, you can bring it to a pressure where the melting point is lower. In both cases, basalt magma will form and considering it is hotter and less dense than the surrounding rock, it will percolate towards the surface and some of that erupts.
Answer:
Explanation:
Given
Both cars mass is m
and solving problem in Vertical and horizontal direction
considering + y and +x to be positive and u be the final velocity of system
Conserving Momentum in Vertical direction

------1
Conserving momentum in x direction
-----2
squaring and adding 1 &2




The correct answer is B. Nitrogen