Afirecracker in a coconut blows the coconut into three pieces. twopieces of equal mass fly off south and west, perpendicular to eachother, at 18 m/s. the third piece has twice the mass asthe other two. part 1 what is the speed of the third piece? (answer in 2 sig figs andm/s)part 2 what is the direction of the third piece? (answer in 2 sig figs anddegrees north of east)

V = 13m/s

North-East (i.e. 45 degree from North)

Explanation:

This question deals with the idea of momentum.

Since the directions of a compass are fixed, we can take south as horizontal and west as vertical. Since both pieces of coconut are of equal mass, then the resultant of the two pieces would be in between South and West and the third piece would be opposite this direction and be in the North-East (i.e. 45 degree from North) direction

To find the speed of the third piece, we first find the speed on the two pieces of the coconut in terms of (horizontal component of velocity) and (vertical component of velocity)

We have

= Velocity in South direction = 18m/s

= Mass of piece in South direction = m

= Velocity in West direction = 18m/s

= Mass of piece in West direction = m

= Velocity of Third Piece in North direction = unknown

= Velocity of Third Piece in East direction = unknown

= Mass of third piece = 2m

Since we now know the horizontal and vertical component of the velocity of the third piece of coconut we find the resultant velocity. Since we know the direction is North-East, we can imagine a right angled triangle with base of 9 and height 9 and the hypotenuse equal to the resultant velocity .

We can simply apply the Pythagoras theorem and find the hypotenuse

V = 13m/s

increases it

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.