Q51. The focal length of a concave lens is 0.5m. The power of the lens is…
(A) +0.5D
(B) -0.5D
(C) +2.0D
(D) -2.0D
Check Answer:
Correct Answer: (D) -2.0D
Explanation:
The power (P) of a lens is defined as the reciprocal of its focal length (f) when the focal length is expressed in meters. The unit of power is the diopter (D).
For a concave lens, the focal length is conventionally considered negative because it is a diverging lens. Therefore, the given focal length of 0.5 m must be written as f = -0.5 m.
Using the formula P = 1/f, the calculation is performed by substituting the negative focal length value: $latex P = \frac{1}{-0.5}$.
BBll ah $$P = \frac{1}{-0.5}$$.
Blah Blah \(P = \frac{1}{-0.5}\)
Performing the calculation yields a power of -2.0 D.
The power of the concave lens is -2.0 D, which corresponds to option (D).
Q52. The rule to determine the direction of a force experienced by a straight current carrying conductor placed in a magnetic field which is perpendicular to it is…
(A) Right-hand thumb rule
(B) Fleming’s left-hand rule
(C) Fleming’s right-hand rule
(D) Hund’s rule
Check Answer:
Correct Answer:
(B) Fleming’s left-hand rule
Explanation:
Exp:
One parsec in astronomical units (A.U.) is about…
(A) $latex 2 \times 10^{3} \text{ A.U.}$
(B) $latex 2 \times 10^{4} \text{ A.U.}$
(C) $latex 2 \times 10^{5} \text{ A.U.}$
(D) $latex 2 \times 10^{6} \text{ A.U.}$
Check Answer:
Correct Answer:
(C) $latex 2 \times 10^{5} \text{ A.U.}$
Explanation:
Exp:
One parsec in astronomical units (A.U.) is about…
(A) $latex 2 \times 10^{3} \text{ A.U.}$
(B) $latex 2 \times 10^{4} \text{ A.U.}$
(C) $latex 2 \times 10^{5} \text{ A.U.}$
(D) $latex 2 \times 10^{6} \text{ A.U.}$
Check Answer:
Correct Answer:
(C) $latex 2 \times 10^{5} \text{ A.U.}$
Explanation:
Exp:
Q51. The focal length of a concave lens is 0.5m. The power of the lens is…
(A) +0.5D
(B) -0.5D
(C) +2.0D
(D) -2.0D
Check Answer:
Correct Answer: (D) -2.0D
Explanation:
The power (P) of a lens is defined as the reciprocal of its focal length (f) when the focal length is expressed in meters. The unit of power is the diopter (D).
For a concave lens, the focal length is conventionally considered negative because it is a diverging lens. Therefore, the given focal length of 0.5 m must be written as f = -0.5 m.
Using the formula P = 1/f, the calculation is performed by substituting the negative focal length value: $latex P = \frac{1}{-0.5}$.
BBll ah $$P = \frac{1}{-0.5}$$.
Blah Blah \(P = \frac{1}{-0.5}\)
Performing the calculation yields a power of -2.0 D.
The power of the concave lens is -2.0 D, which corresponds to option (D).
Q52. The rule to determine the direction of a force experienced by a straight current carrying conductor placed in a magnetic field which is perpendicular to it is…
(A) Right-hand thumb rule
(B) Fleming’s left-hand rule
(C) Fleming’s right-hand rule
(D) Hund’s rule
Check Answer:
Correct Answer:
(B) Fleming’s left-hand rule
Explanation:
Exp:
One parsec in astronomical units (A.U.) is about…
(A) $latex 2 \times 10^{3} \text{ A.U.}$
(B) $latex 2 \times 10^{4} \text{ A.U.}$
(C) $latex 2 \times 10^{5} \text{ A.U.}$
(D) $latex 2 \times 10^{6} \text{ A.U.}$
Check Answer:
Correct Answer:
(C) $latex 2 \times 10^{5} \text{ A.U.}$
Explanation:
Exp:
One parsec in astronomical units (A.U.) is about…
(A) $latex 2 \times 10^{3} \text{ A.U.}$
(B) $latex 2 \times 10^{4} \text{ A.U.}$
(C) $latex 2 \times 10^{5} \text{ A.U.}$
(D) $latex 2 \times 10^{6} \text{ A.U.}$
Check Answer:
Correct Answer:
(C) $latex 2 \times 10^{5} \text{ A.U.}$
Explanation:
Exp: