Answer:
Static friction
Explanation:
When there is contact between two surfaces and there is no movement, there is static friction. So, if we have a book that rests on a wooden table, we have an example of Static friction, where this force avoids the movement of the book.
Answer:
A)
B)
C)
Explanation:
Given that:
- no. of turns i the coil,

- area of the coil,

- time interval of rotation,

- intensity of magnetic field,

(A)
Initially the coil area is perpendicular to the magnetic field.
So, magnetic flux is given as:
..................................(1)
is the angle between the area vector and the magnetic field lines. Area vector is always perpendicular to the area given. In this case area vector is parallel to the magnetic field.


(B)
In this case the plane area is parallel to the magnetic field i.e. the area vector is perpendicular to the magnetic field.
∴ 
From eq. (1)


(C)
According to the Faraday's Law we have:



Answer:
Power = 21[W]
Explanation:
Initial data:
F = 35[N]
d = 18[m]
In order to solve this problem we must remember the definition of work, which tells us that it is equal to the product of a force for a distance.
Therefore:
Work = W = F*d = 35*18 = 630 [J]
And power is defined as the amount of work performed in a time interval.
Power = Work / time
Time = t = 30[s]
Power = 630/30
Power = 21 [W]
<span>The charged balloon will stick to a neutral wall because of the Static Electricity:
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The matter is formed by atoms and these atoms are composed of electrons, protons and neutrons (the electrons have a negative charge, the protons have a positive charge and the neutrons have no charge).
As the balloon is charged (It gained electrons), and the charge of the same sign repel each other, when it approaches the wall, the electrons of this wall will move away, and the positive charges (protons) will remain in the nearest area to the balloon. As the charges of different signs are attracted, the balloon will be stuck to the wall.
I think it's C, three hues that are adjacent on the color wheel