Answer:
Right hand thumb rule : It is a rule used to find the magnetic field direction around current carrying wire .
Explanation:
It states that : "If you grasp conductor in your right hand such that thumb points in upward direction ,then the direction in which our finger curls gives the direction of magnetic field or magnetic lines of forces" .
This rule proves that :Current can give rise to magnetism .
Around every current carrying conductor there exist a magnetic field which can be easily felt .
According to this rule : When a current flows in upward direction ,the finger curls in anticlockwise direction and when direction of current reverses ,then the direction of field also reverses .
Answer:
B) 
Explanation:
The electric force between charges can be determined by;
F = 
Where: F is the force, k is the Coulomb's constant,
is the value of the first charge,
is the value of the second charge, r is the distance between the centers of the charges.
Let the original charge be represented by q, so that;
= 2q
= 
So that,
F = 
x 
= 2q x
x 
=
x 
=
x 
F =
x 
The electric force between the given charges would change by
.
Answer:
1 m
Explanation:
L = 100 m
A = 1 mm^2 = 1 x 10^-6 m^2
Y = 1 x 10^11 N/m^2
F = 1000 N
Let the cable stretch be ΔL.
By the formula of Young's modulus



ΔL = 1 m
Thus, the cable stretches by 1 m.
L<span>ight with a spectral composition that stimulates all three types of the color sensitive </span>cone cells<span> of the </span>human eye<span> in nearly equal amounts appears white.
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It does not move because of the sun the sun has no energy.