Answer:

Explanation:
The Hi line of the Balmer series is emitted in the transition from n = 3 to n = 2 i.e.
and 
The wavelength of Hi line of the Balmer series is given by :




So, the wavelength for this line is 550 nm. Hence, this is the required solution.
Answer:
The base of taller buildings are made broader because it reduces the pressure exerted on the ground so that they do not sink in due to the extremely high pressure of the building.
Explanation:
hope thiss helpss~!
Wind power is produced from the
wind turbines or sails that uses air flow to convert it into mechanical power.
It is an alternative to fossil fuel burning, it is all around, renewable,
clean, produces no greenhouse gases and uses little land. The advantages of
wind power have been greatly praised by many. However, it has disadvantages.
Wind power especially at farm is noisy and may spoil the view for their
neighboring people. Also the amount of electricity depends on the strength of
the wind. If no wind is around, no electricity is produced.
Answer:
v (speed) = S / t = 4 * 400 m / (6 * 60 sec) = 4.4 m/s
The average velocity is zero because there is no net vector displacement.