Answer:
Correct answer is 2B
Explanation:
The electric field magnitude and magnetic field magnitude in an electromagnetic waves are related as under
where 'c' is velocity of light in the medium of transmission
According to the given question if we double the electric field we have
Thus the magnetic field also doubles
Answer: 45.3°
Explanation:
Given,
Length of ladder = l
Weight of ladder = w
Coefficient of friction = μs = 0.495
Smallest angle the ladder makes = θ
If we assume the forces in the vertical direction to be N1, and the forces in the horizontal direction to be N2, then,
N1 = mg and
N2 = μmg
Moment at a point A in the clockwise direction is
N2 Lsinθ - mg.(L/2).cosθ = 0
μmgLsinθ - mg.(L/2).cosθ = 0
μmgLsinθ = mg.(L/2).cosθ
μsinθ = cosθ/2
sin θ / cos θ = 1 / 2μ
Tan θ = 1 / 2μ
Substituting the value of μ = 0.495, we have
Tan θ = 1 / 2 * 0.495
Tan θ = 1 / 0.99
Tan θ = 1.01
θ = tan^-1(1.01)
θ = 45.3°
The girl may hear from the front
The answer would be A, since at that position the Earth is fully/partially being engulfed in a shadow cast by the moon from the sun’s rays.
Hope this helps!
Answer:
measure the vector diagram first
