Answer:The place to go for the answer to such an easy question is the SI Brochure, the document which defines the SI and all its units.
 
        
             
        
        
        
Answer:
Explanation:
There are different theories and evidence about the big bang, in this case, we're going to see three evidence.
The galaxies are moving from us, this means space is expanded, this in consequence Big Bang's explosion.
The cosmic microwave background radiation is related to the early warmth of the universe.
The observed abundance of hydrogen, helium, deuterium, lithium, these are checked from the spectra of the oldest stars.
 
        
             
        
        
        
Answer:
1. Battery
2. Copper wire
3. Nail or piece of metal (zinc, iron, or steel).
 
        
                    
             
        
        
        
Answer:
Explanation:
a ) Slit separation d = .1 x 10⁻³ m
Screen distance D = 4 m
wave length of light  λ = 650 x 10⁻⁹ m
Width of central fringe = λ D / d
= 
= 26 mm
b ) Distance between 1 st and 2 nd bright fringe will be equal to width of dark fringe which will also be equal to 26 mm
c ) Angular separation between the central maximum and 1 st order maximum will be equal to angular width of fringe which is equal to
λ  / d
= 
= 6.5 x 10⁻³ radian.