Correct Answer: C AIDS is caused by HIV (virus). Cholera/typhoid: bacteria, Malaria: protozoa.
Q2. Biology
The enzyme that breaks down proteins in stomach is:
A. Amylase
B. Pepsin
C. Lipase
D. Trypsin
Correct Answer: B Pepsin (in gastric juice) breaks proteins into peptides in acidic medium.
Q3. Chemistry
What is the type of reaction that involves the loss of electrons by a species?
A. Oxidation reaction
B. Reduction reaction
C. Acid-base reaction
D. Neutralization reaction
Correct Answer: A An oxidation reaction is a type of reaction that involves the loss of electrons by a species.
Q4. Physics
The coefficient of performance of a refrigerator is given by:
A. Q/W
B. Q/W
C. W/Q
D. (Q-Q)/W
Correct Answer: B COP = Q/W where Q is heat extracted from cold reservoir and W is work input.
Q5. Physics
The time period of a simple pendulum depends on:
A. Mass of bob
B. Amplitude (small)
C. Length of pendulum
D. Material of bob
Correct Answer: C T = 2pisqrt(L/g). Time period depends only on length and g.
Q6. Physics
Which of the following has the highest specific heat capacity?
A. Iron
B. Copper
C. Water
D. Lead
Correct Answer: C Water has the highest specific heat capacity (4200 J/kg degrees C) among common substances.
Q7. Physics
What is the nature of the force between two parallel current-carrying conductors?
A. Repulsive
B. Attractive
C. Both attractive and repulsive
D. Neutral
Correct Answer: C The force between two parallel current-carrying conductors can be either attractive or repulsive, depending on the direction of the current flow.
Q8. Biology
DNA replication is which type of process?
A. Conservative
B. Semiconservative
C. Dispersive
D. Random
Correct Answer: B DNA replication follows the semiconservative model as demonstrated by Meselson and Stahl.
Q9. Chemistry
Which quantum number determines the shape of orbital?
A. n
B. l
C. m
D. s
Correct Answer: B Azimuthal quantum number (l) determines orbital shape (s->0, p->1, d->2).
Q10. Chemistry
The chemical formula of rust is:
A. FeO
B. FeO
C. FeO.xHO
D. FeO
Correct Answer: C Rust is hydrated iron(III) oxide, FeO.xHO.
Q11. Chemistry
What is the type of bond that occurs between two atoms with a large difference in electronegativity?
A. Covalent bond
B. Ionic bond
C. Hydrogen bond
D. Van der Waals bond
Correct Answer: B Ionic bonds occur between two atoms with a large difference in electronegativity, resulting in the transfer of electrons and the formation of ions.
Q12. Physics
The dimensional formula of force is:
A. [MLT]
B. [MLT^2]
C. [MLT^2]
D. [ML^2T^2]
Correct Answer: C F = ma -> [F] = [M][LT^2] = [MLT^2].
Q13. Physics
What is the phenomenon where an electric current is generated in a conductor when it is exposed to a changing magnetic field?
A. Electromagnetic induction
B. Electrostatic induction
C. Magnetic induction
D. Electric induction
Correct Answer: A Electromagnetic induction is the phenomenon where an electric current is generated in a conductor when it is exposed to a changing magnetic field.
Q14. Physics
When light of frequency is incident on a photocathode, the stopping potential is V. When light of frequency is incident on the same photocathode, the stopping potential is V. If V > V, which of the following relations is correct? (h is Planck's constant, e is the charge of an electron)
A. h( - ) = e(V - V)
B. h( - ) = e(V - V)
C. h( + ) = e(V + V)
D. h( / ) = e(V / V)
Correct Answer: A According to Einstein's photoelectric equation, the maximum kinetic energy of emitted photoelectrons (KE_max) is given by:h = + KE_maxwhere h is Planck's constant, is the frequency of incident light, and is the work function of the metal.The stopping potential (V_s) is related to KE_max by: KE_max = eV_sSo, the equation becomes: h = + eV_sFor the first case:h = + eV (Equation 1)For the second case:h = + eV (Equation 2)Subtract Equation 1 from Equation 2:(h - h) = ( + eV) - ( + eV)h( - ) = eV - eVh( - ) = e(V - V)
Q15. Physics
A force of 10 N acts on a body of mass 2 kg for 5 s. The impulse is:
A. 10 Ns
B. 50 Ns
C. 2 Ns
D. 25 Ns
Correct Answer: B Impulse = F x t = 10 x 5 = 50 Ns.