An object is placed 10cm in front of a concave mirror of focal length 15cm. What is the position and nature of the image formed?
- A. 30cm and virtual
- B. 6cm and real
- C. 6cm and virtual
- D. 30cm and real
To obtain a magnification of 2.5, how far should an object be placed from the pole of a thin converging lens of focal length 10.20m?
- A. 0.13m
- B. 0.25m
- C. 0.28m
- D. 0.50m
Two strings of the same length and under the same tension gives notes of frequencies in the ratio 4 : 1. The masses of the strings are in the corresponding ratio of
- A. 2 : 1
- B. 1 : 2
- C. 1 : 4
- D. 1 : 16
A slight loading of a tuning fork has the effect of
- A. decreasing its amplitude
- B. increasing its amplitude
- C. decreasing its frequency
- D. increasing its frequency
The speed of sound in air at sea level is 340ms\(^{-1}\) while that of light is 300 000kms\(^{-1}\). How far (to the nearest meter) from the center of a thunderstorm is an observer who hears a thunder 2s after a lightning flash?
- A. 170m
- B. 340m
- C. 600m
- D. 680m
Which of the following factors affects the speed of sound in air? i. Temperature ii. pressure iii. Frequency
- A. i only
- B. ii only
- C. i and ii only
- D. ii and iii only
A note is called an octave of another note when
- A. its frequency is twice that of the first note
- B. its frequency is half of the first note
- C. the notes have the same fundamental frequency
- D. its periodic time is twice that of the first note
A piano wire 0.5m long has a total mass of 0.01kg and is stretched with a tension of 800N. Calculate the frequency of the wire when it sounds its fundamental note
- A. 200Hz
- B. 100Hz
- C. 4Hz
- D. 2Hz
Which of the following properties is/are common to all waves? i. Diffraction ii. Refraction iii. Interference
- A. i only
- B. ii only
- C. ii and iii
- D. i, ii, and iii
Which of the following media allow the transmission of sound wave through them i. Air. ii. Liquids. iii. Solids.
- A. i and ii only
- B. i and iii only
- C. ii and iii only
- D. i,ii and iii
When heat is applied to one end of a metal rod, the molecules at the other end soon begin to vibrate with greater amplitude than before because heat has been transferred by
- A. radiation
- B. convection
- C. conduction
- D. evaporation
A tap supplies water at 25oC while another supplies water at 75oC. If a man wishes to bathe with water at 40oC, the ratio of the mass of cold water to the mass of hot water required is
- A. 1 : 3
- B. 15 : 8
- C. 7 : 3
- D. 3 : 1
The amount of heat needed to raise the temperature of 10kg of copper by 1k is its
- A. specific heat capacity
- B. heat capacity
- C. latent heat
- D. internal energy
The product PV where P is pressure and V is volume has the same unit as
- A. force
- B. power
- C. energy
- D. accelaration
A body whose mass is 2kg and has a volume of 500cm3 just floats when completely immersed in a liquid. Calculate the density of the liquid
- A. 4.0 x 102kgm-3
- B. 4.0 x 103kgm-3
- C. 1.0 x 103kgm-3
- D. 1.0 x 106kgm-3
A force, 10N, drags a mass 10kg on a horizontal table with an acceleration of 0.2ms. If the acceleration due to gravity is 10ms-1, the coefficient of friction between the moving mass and the table is
- A. 0.02
- B. 0.08
- C. 0.20
- D. 0.80
How long will it take a 60kg man to climb a height of 22m if he expended energy at a rate of 0.25kW. [g = ms-2]
- A. 5.3s
- B. 34.5s
- C. 41.6s
- D. 52.8s
A 20-toothed gear wheel drives a 60-toothed one. If the angular speed of the smaller wheel is 120 rev s-1, the angular speed of the larger wheel is
- A. 3 rev s-1
- B. 40 rev s-1
- C. 360 rev s-1
- D. 2400 rev s-1
A particle starts from rest and moves with a constant acceleration of 0.5ms-2. The distance covered by the particle in 10s is?
- A. 2.5m
- B. 5.0m
- C. 25.0m
- D. 50.0m
When taking a penalty kick, a footballer applies a force of 30.0N for a period of 0.05s. if the mass of the ball is 0.075kg, calculate the speed with which the ball moves off.
- A. 4.50ms-1
- B. 11.25ms-1
- C. 20.00ms-1
- D. 45.00ms-1
Which of the following quantities are scalars? i. Electrical potential ii. Torque iii. Momentum iv. Kinetic energy
- A. ii and iii only
- B. i and ii only
- C. iii and iv only
- D. i and iv only