the missing force is spring force.
The object is hanging from the spring and the spring is stretched by some distance from its equilibrium position. due to this stretch in the spring , a spring force starts acting on the object trying to regain its equilibrium position.
the spring force is given as
F = kx
where F = spring force ,k = spring constant , x = stretch in the spring.
the spring force balances the weight of the object in down direction and hence keeps the block from falling down.
Snell's law is defined as “The ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant, for the light of a given colour and for the given pair of media”.
Answer:
Isotopes are the elements having the same atomic number i.e same number of protons which in turn is equal to same number of electrons. Number of protons and electrons are equal as the atom is electrically neutral. So, the only option is A.
I hope it helps you !
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Answer: size</h2>
Gel electrophoresis is called to the technique used by scientists for analytical purposes, in life sciences laboratories to separate macromolecules (DNA, RNA, and proteins from various sources).
The process consists of separating the molecules according to their <u>size</u> and <u>electric charge</u>. This is done with a gel (a gelatinous substance extracted from seaweed, called <em>agarose</em>) of controllable porosity placed in an ionic buffer environment. This is how the gel acts as a molecular sieve that separates larger molecules from the smaller ones, because each molecule has different size and charge and will move through the gel at different speeds.
That is, the smaller molecules move more quickly through the gel while the larger ones are left behind.
