Answer:

Explanation:
It is given that,
The number of lines per unit length, N = 900 slits per cm
Distance between the formed pattern and the grating, l = 2.3 m
n the first-order spectrum, maxima for two different wavelengths are separated on the screen by 2.98 mm, 
Let d is the slit width of the grating,



For the first wavelength, the position of maxima is given by :

For the other wavelength, the position of maxima is given by :

So,



or

So, the difference between these wavelengths is 14.3 nm. Hence, this is the required solution.
Can u explain more like ,u have a pic or some?
Answer:
Speed of lighter ball is 4 m/s.
Explanation:
Applying the principle of conservation of linear momentum,
momentum before collision = momentum after collision.

+
= 
- 

= 3 kg,
= 8 m/s,
= 2 kg,
= 0 m/s ( since it is at rest),
= 2 m/s,
= ?
(3 x 8) + (2 x 0) = (8 x 2) - (2 x
)
24 + 0 = 16 - 2
2
= 16 - 24
2
= -8
= 
= -4 m/s
This implies that the light ball moves at the speed of 4 m/s in the opposite direction of the heavier ball after collision.
A cause the sugar cubes are small enough to dissolve fast
There are six distinct changes of phase which happens to different substances at different temperatures. ... Sublimation: the substance changes directly from a solid to a gas without going through the liquid phase. Deposition: the substance changes directly from a gas to a solid without going through the liquid phase.
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