31. In the molecular explanation of conduction, heat is transferred by the
- A. Free electrons
- B. Free atoms
- C. Free molecules
- D. Free solids
32. The conductivity of gases at low pressure can be termed as
I. hot cathode emission
II. thermo ionic emission
III. cold cathode emission
IV. Field emission
- A. I & II
- B. II & III
- C. III & IV
- D. IV & V
33. Which of the following media allow the transmission of sound waves through them?
I. air
II. liquid
III. solids
- A. I & II only
- B. I & III only
- C. II & III only
- D. I, II & III
34. The earth’s gravitational field intensity at its surface is about
(G = 6.7 × 10\(^{-11}\)Nm\(^2\)/kg\(^2\), mass of the earth is 6 × 10\(^{24}\)kg, radius of the earth is 6.4 × 10\(^6\)m, g on the earth = 9.8m/s\(^2\))
- A. 6.7N/kg
- B. 7.9N/kg
- C. 8.0N/kg
- D. 9.8N/kg
35. The following are parts of the eye
I. Retina
II. Pupil
III. Iris
The correct equivalent in the camera in the same order are
- A. Diaphragm, Aperture, film
- B. Aperture, Diaphragm, Film
- C. Film, Diaphragm, Aperture
- D. Film, Aperture, Diaphragm
36. According to kinetic molecular model, in gases
- A. The particles are closely packed together, they occupy minimum space & are usually arranged in a regular pattern
- B. The particles occur in clusters with molecules slightly farther apart
- C. The molecule are very fast apart & occupy all the space made available
- D. The particle vibrate about fixed positions and are held together by the strong intermolecular bonds between them
37. A force of 6N acts horizontally on a stationary mass of 2kg for 4s. The kinetic energy gained by the mass is _________
38. The momentum of a car moving at a constant speed in a circular track
- A. can be both positive and negative
- B. can be zero depending on its position in the track
- C. can be zero depending on its position in the track
- D. a centrifugal
39. A metal rod has a length of 100cm at 200°C. At what temperature will its length be 99.4cm. If the linear expansivity of the material of the nod is 2 × 10\(^{-5}\)C\(^{-1}\)
40. The lead-acid accumulator consists of
- A. lead as the positive electrode
- B. lead acid as the negative electrode
- C. hydrochloric acid as the electrolyte
- D. tetraoxosulphate (vi) acid as the electrolyte
