First answer = brainliestquestion 3 onwards

3. Conservation of momentum for inelastic collisions (the trolleys collide and stick together):

v = (m₁v₁+m₂v₂)/(m₁+m₂)

Given values:

m₁ = m₂ = 1kg

v₁ = 5m/s

v₂ = 0m/s

Substitute the terms in the equation with the given values and solve for v:

v = (1×5+1×0)/(1+1)

4. Apply the same equation for inelastic collisions (the skaters hold on together after the collision):

v = (m₁v₁+m₂v₂)/(m₁+m₂)

m₁ = 60kg (moving skater's mass)

m₂ = 30kg (stationary skater's mass)

v₁ = 6m/s (moving skater's speed)

v₂ = 0m/s (stationary skater is at rest)

Substitute the values and solve for v:

v = (60×6+30×0)/(60+30)

5.

a) Since the car and lorry are moving as one object after the collision, multiply the sum of their masses by their velocity to get their momentum:

p = v×∑m

Given values:

m₁ = 1000kg (sports car)

m₂ = 3000kg (lorry)

v = 25 m/s

Plug in the values and solve for p:

p = 25×(1000+3000)

b) The conservation of momentum guarantees that the total momentum of the objects before and after the collision will be equal. Therefore the total momentum before the collision is the same as the value obtained in the previous question:

c) Assume the lorry was at rest before the collision.

Recall the general equation for conservation of momentum:

m₁v₁ + m₂v₂ = m₁v₁' + m₂v₂'

Given values:

m₁ = 1000kg (sports car)

m₂ = 3000kg (lorry)

v₂ = 0m/s (lorry is initially at rest)

v₁' = v₂' = 25m/s (car and lorry stick together after collision, moving at the same speed)

Plug in the given values and solve for v₁ (car's speed before the collision):

1000v₁ + 3000×0 = 1000×25 + 3000×25

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.

it was given as a lesson and guide for prayer.