Describe how specific elements can be identified in a particular spectra

Every element has a unique energy which helps in identifying it by its spectra

Explanation:

In emission spectra, bright lines will show up corresponding to the difference between energy levels of the elements, where in an absorption spectrum, the lines will be dark.

When an atom absorbs energy, its electrons jump to higher energy levels. ... Each transition has a specific energy difference. This collection of transitions makes up an emission spectrum. These emission spectra are as distinctive to each element as fingerprints are to people.

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s