Destructive force
It’s a force that slowly wears away mountains and other features on earths surface, such as erosion.
Answer:
If the absorbed beam is monochromatic (one wavelength) then it excites the H atom to some state n.
When that state decays, some of the atoms may decay to state 1, others to state 2, and still others to state 3
The net energy emitted in such a case would depend on:
n -1, n - 2, n - 3 which would produce 3 different wavelengths
Answer:

Explanation:
Given:
- mass attached to the rope,

- given time,

function of height of the mass connected via a rope:
differentiate the above eq. with respect to time t gives us the velocity in vertical direction:


put the value of given time:


- As we know form the Newton'a second law of motion that the rate of change in momentum is proportional to the applied force.



Answer:
Explanation:Gravity is what holds the planets in orbit around the sun and what keeps the moon in orbit around Earth. The gravitational pull of the moon pulls the seas towards it, causing the ocean tides. Gravity creates stars and planets by pulling together the material from which they are made.