In the network shown above, determine the potential difference across the 5µF capacitor
- A. 3V
- B. 6V
- C. 12V
- D. 18V
The current I in the fig above is
- A. 4.00A
- B. 1.30A
- C. 0.80A
- D. 0.75A
Two mirrors M1 and M2 are inclined at right angles as shown above calculate the angle of reflection of the ray of light at M2
- A. \( 30^{\circ} \)
- B. \( 45^{\circ} \)
- C. \( 60^{\circ} \)
- D. \( 90^{\circ} \)
In the fig above,A lever of length 200m is used to lift a load of mass 180kg. The pivot at P is 20m from the load. what minimum force F must be applied at the end of the lever [g = 10ms-2]
- A. 9N
- B. 18N
- C. 20N
- D. 200N
The diagram above shows a velocity time graph representing the motion of a car. Find the total distance covered during the acceleration and retardation of the motion
- A. 75m
- B. 150m
- C. 300m
- D. 375m
The kinetic theory of photoelectron liberated from a metallic surface depends on the
- A. intensity of the incident radiation
- B. time duration of the incident radiation
- C. temperature of the incident radiation
- D. frequency of the incident radiation
An element X of an atomic number 88 and mass number 226 decays to form an element Z by emitting two beta particles and an alpha particle. Z is represented by
- A. \(^{222}_{82}Z\)
- B. \(^{222}_{88}Z\)
- C. \(^{226}_{86}Z\)
- D. \(^{226}_{80}Z\)
Which of the following are produced after a nuclear fusion process? i. one heavy nucleus. ii. neutrons-1. iii. protons. iv. Energy.
- A. i and ii
- B. i and iv
- C. ii and iii
- D. ii and iv
Natural radioactivity is the random spontaneous disintegration of the nuclei of heavy isotopes of certain elements with the emission of
- A. \(\alpha\), X, and \( \beta\)
- B. \(\alpha\), \(\beta\) and \(\gamma\)-rays
- C. X, \(\alpha\), \(\gamma\)-ray
- D. \(\alpha\), \( \beta\) and X-rays
Which of the following statements correctly describe(s) cathode rays? i. they consist of tiny particles carrying negative electric charges. ii. they are deflected in a magnetic field but not in an electric field. iii. they consist of fast moving neutrons and deflected in an electric field.
- A. i only
- B. ii only
- C. i and ii only
- D. ii and iii only
Determine the inductive reactance when a 30.0mH inductor with a negligible resistance is connected to a 1.3 x 103Hz oscillator.
- A. 39.0\(\Omega\)
- B. 122.5\(\Omega\)
- C. 245.0\(\Omega\)
- D. 39000.0\(\Omega\)
The primary aim in high tension transmission is to
- A. minimize electrical energy losses due to heat production
- B. increase the rate of energy transfer by using high voltage
- C. increase the current in the wire
- D. generate electricity at high current and low voltage
Which of the following devices may be used to step up the voltage in a d.c. circuit?
- A. a step-up transformer
- B. a d.c. generator
- C. a wattmeter
- D. an induction coil
A 40-W instrument has a resistance of 90\(\Omega\). On what voltage should it be operated normally?
- A. 60V
- B. 150V
- C. 225V
- D. 3600V
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
A current of 100mA passes through a conductor for 2 minutes. The quantity of electricity transported is
- A. 200C
- B. 50C
- C. 12C
- D. 0.002C
The terminal voltage of a battery is 4.0V when supplying a current of 2.0A, and 2.0V when supplying a current of 3.0A. The internal resistance of the battery is
- A. 0.5 \(\Omega\)
- B. 1.0\(\Omega\)
- C. 2.0\(\Omega\)
- D. 4.0\(\Omega\)
A simple cell with mercury-amalgamated zinc electrode prevents
- A. local actions
- B. polarization
- C. buckling
- D. degradation
A current carrying conductor experiences a force when placed in a magnetic field because the
- A. conductor is magnetized
- B. magnetic field of the current interacts with external magnetic field
- C. force is due to the motor principle
- D. electric field of the current interacts with the external magnetic field
Which of the following correctly explains why soft iron is proffered to steel in electromagnets? i. soft iron is more readily magnetized than steel. ii. soft iron is more readily demagnetized than steel. iii. soft iron retains magnetism more than steel.
- A. i only
- B. ii and iii only
- C. i and ii only
- D. i, ii, and iii.
Which of the following correctly explain(s) why a green leaf appears green in bright day light? i. it absorbs only the green component of sunlight. ii. it absorbs all colour of sunlight except green. iii. it reflects only the green component of sunlight.
- A. i only
- B. ii only
- C. i and iii only
- D. ii and iii only