In the fig above, M and N are insulated metal spheres in contact. A negatively charged ebonite rod P is I brought near M. When M and N are Separated and the rod is taken away, which of the following statements is correct
- A. both M and N have acquired negative charges
- B. both M and N have acquired positive charges
- C. M has acquired negative charge and N positive charge
- D. N has acquired negative charge and M positive charge
In the above, a voltage V is applied across the terminals P and Q. The voltage across the 1 ohm resistor is
- A. V/8
- B. V/4
- C. V/3
- D. V/2
fig above represents the main sequence of energy conversion at kainji dam. what is the efficiency of the system?
- A. \(\frac{Q_1}{Q_2}\)
- B. \(\frac{E}{Q_1}\)
- C. \(\frac{E}{Q_1 - Q_2}\)
- D. \(\frac{E}{Q_1 + Q_2}\)
A 50kg block is dropped from a point 10m above as shown in the fig above. if the force constant of the spring is 4.0 x 10\(^4\)Nm-1, find the maximum compression of the spring
[g = 10ms-2]
- A. 1.25m
- B. 0.50m
- C. 0.25m
- D. 0.05m
the fig above shows two connected bodies of masses M\(_1\) and M\(_2\) in equilibrium under gravity. The tension in the upper string is
- A. (m\(_1\)-m\(_2\))g
- B. m\(_1\)g
- C. m\(_2\)g
- D. (m\(_1\)+m\(_2\))g
The velocity time graph above describes the motion of a particle between two points P and Q. What is the distance between P and Q?
- A. 17.0m
- B. 18.0m
- C. 22.5m
- D. 30.0m
A radioactive sample initially contains N atoms. After three half-lives the number of atoms that have disintegrated is
- A. \(\frac{N}{8}\)
- B. \(\frac{3N}{8}\)
- C. \(\frac{5N}{8}\)
- D. \(\frac{7N}{8}\)
Isotopes are nuclei which have
- A. the same number of nuetrons and electrons
- B. equal number of electrons and protons
- C. the same atomic number but different number of neutrons
- D. the same number of total particles
Which of the following statements is TRUE of photoelectric effect?
- A. it cannot occur in liquids
- B. the energy of the emitted electrons is independent of the work function of the surface
- C. the energy of the emitted electron depends on the wavelength of the incident light
- D. the greater the intensity of the incuident light, the greater the incident of the emitted electron
What type of reaction is represented by the following scheme? \( ^2 _1X \) + \( ^{2} _{1}Y \) + \( ^{3} _{2}Z \) + \( ^{1} _{0}n \) + energy
- A. Fusion reaction
- B. Fission reaction
- C. Chain reaction
- D. Radioactive decay
A galvanometer of resistance 20\(\Omega\) is to be provided with a shunt that \(\frac{1}{10}\) of the whole current in a circuit passes through the galvanometer. The resistance of the shunt is
- A. 2.00\(\Omega\)
- B. 2.22\(\Omega\)
- C. 18.00\(\Omega\)
- D. 18.22\(\Omega\)
When two parallel wires carry currents in opposite directions, the force on either wire is
- A. away from the other wire
- B. zero, because the currents cancel each other
- C. twice as much as when the currents are in the same direction
- D. towards the other wire
The direction of the magnetic field at a point in the vicinity of a bar magnet is
- A. always towards the north pole of the magnet
- B. always away from the south pole of the magnet
- C. along the line joining the point to the neutral point
- D. in the direction the north pole of a compass needle would point
A current of 0.5A flows through a resistor when connected to a 40-V battery. How much energy is dissipated in 2 minutes?
- A. 1200J
- B. 1500J
- C. 2400J
- D. 96000J
When a transformer has more secondary windings than primary windings, it?
- A. has a smaller secondary current
- B. has a greater power output
- C. is a step-down transformer
- D. increases the total energy output
Two capacitance of 6\(\mu\)F and 8\(\mu\)F are connected in series. What additional capacitance must be connected in series with this combination to give a total of 3\(\mu\)F
- A. 3\(\mu\)F
- B. 16\(\mu\)F
- C. 24\(\mu\)F
- D. 30\(\mu\)F
If the angle of declination in a place is 10oE, calculate the true geographic bearing if the compass reads N40oE
- A. N50oE
- B. N40oE
- C. N30oE
- D. N25oE
Four lenses are being considered for use as a microscope objective. Which of the following focal lengths is most suitable?
- A. -5mm
- B. +5mm
- C. -5cm
- D. +5cm
A ray of light is incident at an angle of 30o on one top surface of a parallel-sided glass block of refractive index 1.5. The ray finally emerges from the lower surface. What is the angular deviation of the emergent ray?
- A. 60o
- B. 39o
- C. 28o
- D. 0o
A pool of water appears to be 1.0m deep when viewed vertically from above. If the refractive index of water is 1.33, what is the actual depth of the pool?
- A. 0.750m
- B. 1.013m
- C. 1.330m
- D. 13.3000m
An object 3.0cm high is placed 60.0cm from a converging lens whose focal length is 20.0cm. Calculate the size of the image formed
- A. 0.5cm
- B. 1.5cm
- C. 2.0cm
- D. 6.0cm