Everything with 1 symbol = Element
Everything with multiple symbols = Compound
Elements are the smallest particles (if we go further things start to get weird). Compounds are ALWAYS made up from elements.
Answer:
Time will be 2.13 sec
Explanation:
We have given that distance r = 14.3 cm =
Coefficient of static friction 
Angular acceleration is given by 
We know that frictional force is given by 
And centrifugal force is given by 
When coin just starts moving

We know that
, here
is angular velocity
According to first equation of motion we know that

As 
so 




a) When the screen is moved closer towards the slit, the interference fringes will overlap on one another, resulting in an interference pattern that is less sharp and has low intensity
b) When the red filter is replaced with a blue filter, the width of the fringes would decrease. This means that the fringes would be closer and the pattern becomes narrower.
Force applied to overcome friction is 30•9.81•0.25=73.575N
Work is F•d
W=73.575•4.5=331.0875J