A force of 5N act at a point Y on a rod XYZ as shown in the diagram above, if XY is 2m. What is the moment of the force about point X?
- A. 0Nm
- B. 3Nm
- C. 7Nm
- D. 10Nm
What is the average velocity of the sprinter whose velocity time graph is as shown above
- A. 85.0ms-1
- B. 17.0ms-1
- C. 8.5ms-1
- D. 1.7ms-1
Two horizontal forces, 10N and 8N and another force F1 inclined at 30 to the vertical acting as shown in the diagram above, keep the body P in equilibrium, The weight of the body is
- A. 2√3/3N
- B. √2N
- C. 4√3/3
- D. 2V3N
What is the reading of the vernier scale above
- A. 1.88cm
- B. 1.80cm
- C. 1.28cm
- D. 1.97cm
The photocell works on the principle of the
- A. voltaic cell
- B. emision of electrons by incident radiation
- C. emision of protons by incident electrons
- D. photographic plate
A substance has a half of 3mins. after 6mins. the count rate was observed to be 400. What was its count rate at zero time?
- A. 200
- B. 1200
- C. 1600
- D. 2400
What precaution should a manufacturer take to ensure that energy loss in a transformer is minimized?
- A. the winding of the transformer should be made of high resistance wire
- B. the core should be made of thin sheets of metal
- C. no magnetic material should be used to make the core
- D. the flux linking the primary with the secondary coils should be minimum
The number of neutrons contained in the nucleus \(^{238}_{92}U\) is
- A. 92
- B. 146
- C. 238
- D. 330
A 0 – 10mA galvanometer with a coil resistance of 30\(\Omega\) can be converted to a 0 – 10A ammeter by using
- A. 0.03\(\Omega\) series resistor
- B. 0.03\(\Omega\) shunt resistor
- C. 9.99\(\Omega\) shunt resistor
- D. 9.99\(\Omega\) series resistor
A lamp is rated 240V, 60W. The resistance of the filament is
- A. 960\(\Omega\)
- B. 16\(\Omega\)
- C. 15\(\Omega\)
- D. 4\(\Omega\)
Electrical power is transmitted at a high voltage rather than low voltage because the amount of energy loss is reduced due to
- A. heat dissipation
- B. production of eddy currents
- C. excessive current discharge
- D. excessive voltage distance
Which of the following is most suitable for protecting the circuit of 2000W electric iron connected to a 250V mains?
- A. 13A
- B. 8A
- C. 5A
- D. 3A
Which of the following is an essential physical property of the wires used for making fuses?
- A. low density
- B. high thermal conductivity
- C. low electrical resistivity
- D. low melting point
The total energy required to send a unit positive charge round a complete electrical circuit is the
- A. kinetic energy
- B. potential difference
- C. electromotive force
- D. electrical energy
When a known standard resistor of 2\(\Omega\) is connected to the 0.0cm end of a meter bridge, the balance point is found to be at 55.0cm. What is the value of the unknown resistor?
- A. 1.10\(\Omega\)
- B. 1.64\(\Omega\)
- C. 2.44\(\Omega\)
- D. 27.50\(\Omega\)
Three cells each of e.m.f. 1.5v and an internal resistance of 1.0\(\Omega\) are connected in parallel across a load resistance of 2.67\(\Omega\). Calculate the current in the load?
- A. 0.26A
- B. 0.41A
- C. 0.50A
- D. 0.79A
Which of the following is a vector?
- A. Electric charge
- B. Electric field
- C. Electrical potential difference
- D. Electrical capacitance
Which of the following statements are true of an insulated charged body carrying positive charge? i. it contains excess positive charges. ii. it creates an electric field. iii. it possesses potential energy. iv. it carries electric current.
- A. i and iv only
- B. i and ii only
- C. i, ii, iii only
- D. i, ii, iii and iv
One of the properties of the earth’s magnetic field is that the
- A. north pole lies in the northern hemisphere
- B. geographic and magnetic meridians coincide
- C. earth's magnetic flux is entirely horizontal at a place where the magnetic dip is zero
- D. earth's magnetic flux is entirely vertical at a place where the magnetic dip is zero
A sonometer wire of length 100cm under a tension of 10N, has a frequency of 250Hz. Keeping the length of the wire constant, the tension is adjusted to produce a new frequency of 350Hz. The new tension is
- A. 5.1N
- B. 7.1N
- C. 14.0N
- D. 19.6N
An organic pipe closed at one end is 80cm long. Determine the frequency of the fundamental note assuming that the speed of sound in air is 340ms-1
- A. 106Hz
- B. 213Hz
- C. 318Hz
- D. 425Hz