Answer:
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Answer:
Frequency of the light will be equal to 
Explanation:
We have given wavelength of the light 
Velocity of light is equal to 
We have to find the frequency of light
We know that velocity is equal to
, here
is wavelength and f is frequency of light
So frequency of light will be equal to 
So frequency of the light will be equal to 
Mass of yellow train, my = 100 kg
Initial Velocity of yellow train, = 8 m/s
mass of orange train = 200 kg
Initial Velocity of orange train = -1 m/s (since it moves opposite direction to the yellow train, we will put negative to show the opposite direction)
To calculate the initial momentum of both trains, we will use the principle of conservation of momentum which
The sum of initial momentum = the sum of final momentum
Since the question only wants the sum of initial momentum,
(100)(8) + (200)(-1) = 600 m/s