Answer: Acceleration
Detailed Explanation:
Acceleration is defined as the rate of change of velocity.
when a hole is made at the bottom of the container then water will flow out of it
The speed of ejected water can be calculated by help of Bernuolli's equation and Equation of continuity.
By Bernoulli's equation we can write

Now by equation of continuity


from above equation we can say that speed at the top layer is almost negligible.

now again by equation of continuity


here we have


now speed is given by


The alpha line in the Balmer series is the transition from n=3 to n=2 and with the wavelength of λ=656 nm = 6.56*10^-7 m. To get the frequency we need the formula: v=λ*f where v is the speed of light, λ is the wavelength and f is the frequency, or c=λ*f. c=3*10^8 m/s. To get the frequency: f=c/λ. Now we input the numbers: f=(3*10^8)/(6.56*10^-7)=4.57*10^14 Hz. So the frequency of the light from alpha line is f= 4.57*10^14 Hz.