The proof that the earth is rotating is the happens of night and day also the seasons, eg. winter, summer, autumn.
Answer:

Explanation:
As per the formula of thermal expansion we know that

so here we will have



so here change in the length of the rod is given as




Answer:
1. 
2. 
3. 
Explanation:
Given:
- mass of slinky,

- length of slinky,

- amplitude of wave pulse,

- time taken by the wave pulse to travel down the length,

- frequency of wave pulse,

1.



2.
<em>Now, we find the linear mass density of the slinky.</em>


We have the relation involving the tension force as:




3.
We have the relation for wavelength as:



Answer:
The metal will melt but their will be no change in temperature.
Explanation:
The metal is at its melting temperature which means it is still in solid phase but have to cross the enthalpy of its condensation at this same temperature to convert into liquid phase.
<u>On supplying heat, the metal's temperature will not change as the heat will be required as enthalpy of condensation to melt the solid to liquid at the melting temperature.</u>
Answer:
9. The Sun's Gravity
10. The core is the densest layer