Two resistance wires of same material and same length have diameters in ratio 2:1. Their resistances are in ratio MCQ with Answer and Explanation

Two resistance wires of same material and same length have diameters in ratio 2:1. Their resistances are in ratio
A. 2:1
B. 1:2
C. 1:4
D. 4:1
Answer: Option C
Solution (By JKSSB Mock Tests)
R ∝ L/A ∝ 1/d². So R₁/R₂ = (d₂/d₁)² = (1/2)² = 1/4 = 1:4.

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The work done in moving a unit positive charge between two points in an electric field is called:
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Correct Answer: Option A


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A projectile is fired at an angle of 45 degrees to the horizontal. The ratio of its maximum height to its horizontal range is:
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Correct Answer: Option C


Explanation:
The maximum height H = (u^2 * sin^2(theta)) / 2g. The horizontal range R = (u^2 * sin(2theta)) / g. For an angle of 45 degrees, sin(45) = 1/sqrt(2) and sin(90) = 1. H = (u^2 * 0.5) / 2g = u^2 / 4g. R = u^2 / g. Therefore, H/R = (u^2/4g) / (u^2/g) = 1/4. The ratio is 1:4.

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