To understand why the correct choice is "Statement-I is false but Statement-II is true", we need to examine each statement individually.
Statement-I: "The equivalent emf of two nonideal batteries connected in parallel is smaller than either of the two emfs."
When two nonideal batteries are connected in parallel, the equivalent emf (Eeq) is not simply smaller than either emf but rather an average based on their internal resistances. The formula for the equivalent emf is:
Eeq= (E1R2 + E2R1)/(R1+R2)
Here, E1 and E2 are the emfs of the two batteries, while R1 and R2 are their internal resistances. The Eeq is essentially a weighted average and can be greater than or equal to the smaller emf and smaller than or equal to the larger emf. Therefore, Statement-I is false.
Statement-II: "The equivalent internal resistance of two nonideal batteries connected in parallel is smaller than the internal resistance of either of the two batteries."
When internal resistances are combined in parallel, the equivalent resistance (Req) is smaller than either of the individual resistances. The formula for the equivalent internal resistance is:
1/Req = 1/R1 + 1/R2
As a result, Req is indeed smaller than either R1 or R2. Therefore, Statement-II is true.
Thus, the correct answer is: Statement-I is false but Statement-II is true.
Match List - I with List - II:
List - I:
(A) Electric field inside (distance \( r > 0 \) from center) of a uniformly charged spherical shell with surface charge density \( \sigma \), and radius \( R \).
(B) Electric field at distance \( r > 0 \) from a uniformly charged infinite plane sheet with surface charge density \( \sigma \).
(C) Electric field outside (distance \( r > 0 \) from center) of a uniformly charged spherical shell with surface charge density \( \sigma \), and radius \( R \).
(D) Electric field between two oppositely charged infinite plane parallel sheets with uniform surface charge density \( \sigma \).
List - II:
(I) \( \frac{\sigma}{\epsilon_0} \)
(II) \( \frac{\sigma}{2\epsilon_0} \)
(III) 0
(IV) \( \frac{\sigma}{\epsilon_0 r^2} \) Choose the correct answer from the options given below:
Consider the following statements:
A. Surface tension arises due to extra energy of the molecules at the interior as compared to the molecules at the surface of a liquid.
B. As the temperature of liquid rises, the coefficient of viscosity increases.
C. As the temperature of gas increases, the coefficient of viscosity increases.
D. The onset of turbulence is determined by Reynolds number.
E. In a steady flow, two streamlines never intersect.
Choose the correct answer from the options given below: