In a compound microscope, the image formed by the objective lens is at a distance of 3.0cm from the eye lens. Calculate the focal length of the eye lens
- A. 0.3cm
- B. 2.7cm
- C. 3.4cm
- D. 8.3cm
A converging lens of focal length 15cm forms a virtual image at a point 10cm from the lens. Calculate the distance of the object from the lens
- A. 10.00cm
- B. 6.00cm
- C. 5.00cm
- D. 1.50cm
The refractive index of a medium relative to air is 1.8. Calculate to the nearest degree, the critical angle for the medium
- A. 68o
- B. 56o
- C. 34o
- D. 18o
The size of the hole of a pin hole camera is increased. The resultant image formed becomes
- A. sharper
- B. reduced in size
- C. enlarged
- D. blurred
In the wave equation y = Eo, sin(299t – \(\pi\)), Eo represents the
- A. amplitude
- B. frequency
- C. period
- D. wavelength
A radio wave has a wavelength of 150m. If the velocity of radio waves is free spaces is 3 x 10\(^8\) ms\(^{-1}\), calculate the frequency of the radio wave
- A. 4.50 x 1010Hz
- B. 5.0 x 109Hz
- C. 4.5 x 109Hz
- D. 2.0 x 106Hz
A slinky spring fixed at one end is placed horizontally on a table. The free end is displaced parallel to the table and then released. The resultimg wavelength is
- A. transverse
- B. longitudinal
- C. stationary
- D. electromagnetic
What type of motion does the skin of a ‘talking’ drum perform when it is struck with a drum stick?
- A. Random
- B. Rational
- C. Translational
- D. vibratory
Calculate the energy required to vapourise 50g of water initially at 80oC.[specific heat capacity of water = 4.2Jg-1K-1][specific latent heat of vaporisation of water = 2260Jg-1]
- A. 113,000J
- B. 117,200J
- C. 234,400J
- D. 420,000J
Water of mass 120g at 50oC is added to 200g of water at 10oC and the mixture is well stirred. Calculate the temperature of the mixture. [Neglect heat losses to the surrounding]
- A. 60oC
- B. 40oC
- C. 25oC
- D. 10oC
The silver coating on the inside of a vacuum flask reduces heat loss by
- A. conduction
- B. radiation
- C. condensation
- D. convention
The ice and steam points of a certain thermometer are -20° and 100° respectively. Calculate the Celsius temperature corresponding to 70° on the thermometer
- A. 84.0o
- B. 75.0o
- C. 64.0o
- D. 58.0o
Which of the following actions will improve the efficiency of the pulley system?
- A. reducing the mass of the pulley
- B. increasing the friction force between the string and the pulley
- C. increasing the mass per unit length of the string of the pulley
- D. increasing the mass of the pulley
A block and tackle system has 6 pulleys. If the efficiency of the machine is 60%, determine its mechanical advantages
- A. 12.0
- B. 10.0
- C. 3.6
- D. 1.8
a load of mass120kg is raised vertically through a height of 2m in 30s by a machine whose efficiency is 100%. Calculate the power generated by the machine. [g = 10ms-2]
- A. 60W
- B. 80W
- C. 100W
- D. 120W
Which of the following statements correctly defines quantitatively the work done by a force? the product of the force and the distance moved
- A. parallel to the line of action of the force from a reference point
- B. perpendicular to the line of action of the force from a reference point
- C. on a line through the reference point
- D. by the object
In the diagram above, AB represents a uniform rod of length 1.50m which is in equilibrium on a pivot at P, If AP = 40cm, calculate the mass of the rod. [g = 10ms-2]
- A. 0.280kg
- B. 0.400kg
- C. 0.613kg
- D. 0.800kg
A spiral spring of natural length 30.0cm and force constant of 20Nm-1 is compressed to 20.0cm. Calculate the energy stored in the spring
- A. 0.1J
- B. 1.0J
- C. 10.0J
- D. 100.0J
An object A is held in equilibrium as illustrated in the diagram above. Using the data on the diagram determine the magnitude, W of the weight of
- A. 23N
- B. 17N
- C. 7N
- D. 5N
An object is acted upon by a system of parallel forces causing the object to be in static equilibrium. Which of the following statements is not correct?
- A. The resultant of the parallel force is zero
- B. the algebraic sum of the moment of the forces is zero
- C. all the parallel forces must be equal in magnitude and in direction
- D. the sum of the forces in one direction must be equal to the sum of forces in the opposite direction
An object is released from rest at a height of 25m. Calculate the time it takes to fall to the ground. [g = 10ms-2]
- A. 25.00s
- B. 10.00s
- C. 2.50s
- D. 2.24s