Physics Past Questions And Answers
Two metals P and Q of length l1 and l2 are heated through the same temperature difference. If the ratio of the linear expansivities of P to Q is 2:3 and the ratio of lengths is 3:4. What is the ratio of increase in length of P to Q?
- A) 7:5
- B) 5:7
- C) 1:2
- D) 2:1
Which of the following statements about anomalous expansion of water are correct? i. There is contraction between 0oC and 4oC. ii. There is expansion between 0oC and 100oC. iii. The volume is minimum at 4oC. iv. The volume is maximum at 4oC
- A. i and ii only
- B. ii and iii only
- C. i and iii only
- D. ii and iv only
A nuclide \(^{202}_{84} Y\) emits in succession an \(\alpha-particle\) and a \(\beta-particle\). The atomic number of the resulting nuclide is
- A. 198
- B. 83
- C. 82
- D. 80
A certain radioactive source emits radiation that was found to be deflected by both magnetic and electric fields. The radiation is?
- A. beta rays
- B. gamma rays
- C. x-rays
- D. ultra-violet rays
What is the angle of dip at the magnetic equator
- A. 45°
- B. 0°
- C. 90°
- D. 180°
A parallel plate capacitor of area 10cm2 in vacuum has a capacitance of 10-2\(\mu\)F. What is the distance between the plates?(e = 9 x 10-12fm)
- A. 9 x 10-13m
- B. 9 x 10-7m
- C. 9 x 10-3m
- D. 9 x 107m
Magnetic flux density is defined as the
- A. total number of magnetic lines of force surrounding a magnet
- B. number of magnetic lines of force per unit area normal to the magnetic field
- C. strength of the magnetic field surrounding a current-carrying conductor
- D. magnetic force exerted on a unit magnetic pole
A sonometer wire of linear density 0.08kg m-1 subjected to a tension of 800N is plucked. Calculate the speed of a pulse which moves from one end of the wire to the other
- A. 179.0ms-1
- B. 100.0ms-1
- C. 15.8ms-1
- D. 8.0ms-1
A planet has mass, M, and radius R, If the universal gravitational constant is G, what is the expression for the escape velocity of an object on the planet?
- A. \(\frac{\sqrt{GR}}{2}\)
- B. \(\frac{\sqrt{2GM}}{R}\)
- C. \(\frac{\sqrt{2G}}{R}\)
- D. \(\frac{\sqrt{GM}}{R}\)
Light of velocity 3 x 108ms-1 is incident on a material of reflective of index n. If the velocity of light is reduced to 2.4 x 108ms-1 in the material, what is n?
- A. 2.33
- B. 2.25
- C. 1.33
- D. 1.25