Find the wavelength of the balmer series spectral line corresponding to n = 15.

371.2 mm

Explanation:

The Balmer series of spectral lines is obtained from the formula

1/λ = R(1/2² -1/n²) where λ = wavelength, R = Rydberg's constant = 1.097 × 10⁷ m⁻¹

when n = 15

1/λ = 1.097 × 10⁷ m⁻¹(1/2² -1/15²)

    = 1.097 × 10⁷ m⁻¹(1/4 -1/225)

    = 1.097 × 10⁷ m⁻¹(0.25 - 0.0044)

    = 1.097 × 10⁷ m⁻¹ 0.245556

    = 2.693 10⁶ m⁻¹

So,

λ  = 1/2.693 10⁶ m⁻¹

    = 0.3712 10⁻⁶ m

    = 371.2 mm

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.

higher potential

explanation:

because it is in a high speed so it must move into a of high potential