At which position should an object be placed in front of a concave mirror in order to obtain an image which is of the same size as the object?
- A. at the centre of curvature
- B. at the principal focus
- C. between the pole and principal focus
- D. between the centre of curvature and principal focus
The equation of a certain progressive transverse wave is y = 2 sin 2 \(\pi ( \frac{t}{0.01} – \frac{x}{30})\), where x and y are in cm and t in seconds. Calculate the period of the wave.
- A. 0.001s
- B. 0.010s
- C. 10.000s
- D. 100.000s
When salt is dissolved in water, the freezing point of the water
- A. increases
- B. decreases
- C. remains the same
- D. increases and later decrease
An electric heater has a resistance of 50\(\Omega\). When it is immersed in water and connected to mains source, it draws a current of 4.0A. Calculate the heat gained by the water if the heater is switched on for 2 minutes, assuming no heat losses to the surroundings
- A. 4200J
- B. 1600J
- C. 24000J
- D. 96000J
Ice of mass 10g at 5°C was completely converted to water at 0°C, calculate the quantity of heat used. [specific heat capacity of ice = 2.1 Jg\(^{-1}\)K\(^{-1}\), specific latent heat of fusion of ice = 336 Jg\(^{-1}\)]
- A. 105J
- B. 3255J
- C. 3465J
- D. 16821J
The volume of a given mass of gas at 27oC and 800 mmHg is 76cm2. Calculate its volume at s.t.p
- A. 100.0 cm3
- B. 72.8 cm3
- C. 60.0 cm3
- D. 36.4 cm3
Highly polished silvery surfaces are
- A. poor absorbers and poor emitters of radiation
- B. poor absorbers and good emitters of radiation
- C. good absorbers and poor emitters of radiation
- D. good absorbers and good emitters of radiation
The magnitude of the expansion or contraction of a substance depends on the i. temperature change ii. nature of the substance iii. size of the substance. Which of the statements above are correct?
- A. i and ii only
- B. ii and iii only
- C. i and iii only
- D. i, ii and iii
Which of the following types of thermometer is used for the calibration of other thermometers?
- A. liqud-in-glass thermometer
- B. constant volume gas thermometer
- C. optical pyrometer
- D. thermocouple
The velocity ratio of an inclined plane
- A. increases with increase in the angle of inclination
- B. increases with decrease in the angle of inclination
- C. decreases with decrease in the angle of inclination
- D. is independent of the angle of inclination
A body of mass 11kg is suspended from a ceiling fan by an aluminum wire of length 2m and diameter 2mm. Calculate the elastic energy stored in the wire [Young’s modulus of aluminum is 7.0 x \(10^10Nm^{-2}\), g = 10m\(s^{-2}\), \(\pi\) = 3.142]`
- A. 1.1 x 10-1J
- B. 5.5 x 10-2J
- C. 1.1 x 10-4J
- D. 5.5 x 10-8J
From Newton’s first law of motion,
- A. a body can only undergo translational motion
- B. once a body remains at rest no force acts on it
- C. the net force acting in uniform linear motion is zero
- D. a body's inertia is its weight
The maximum displacement on either side of the equilibrium position of an object in simple harmonic motion represents
- A. period
- B. amplitude
- C. wavelength
- D. frequency
A body of mass 20g projected vertically upwards in vacuum returns to the point of projection after 1.2s. [g = 10ms-2]. Determine the potential energy of the body at the maximum height of its motion
- A. 0.36J
- B. 0.72J
- C. 360.00J
- D. 720.00J
A body of mass 20g projected vertically upwards in vacuum returns to the point of projection after 1.2s. [g = 10ms\(^{-2}\)]. Calculate the speed of projection
- A. 1.2ms-1
- B. 6.0ms-1
- C. 12.0ms-1
- D. 0.6ms-1
The total area under a force-velocity graph represents
- A. energy
- B. momentum
- C. power
- D. pressure
A body of mass 2kg is released from rest on a plane inclined at an angle of 60° to the horizontal. Calculate the acceleration of the body down the plane.[g = 10ms\(^{-2}\)]
- A. 3.1ms-2
- B. 5.2ms-2
- C. 6.0ms-2
- D. 8.7ms-2
The slope of a linear distance-times graph represents
- A. acceleration
- B. displacement
- C. speed
- D. velocity
Solid friction, like viscosity is
- A. independent of the surface area in contact
- B. independent of the relative motion between layers
- C. dependent on normal reaction
- D. in opposition to motion
Which of the following statements about pressure in a liquid is correct?
- A. the pressure in a liquid increases with depth
- B. the higher the density of a liquid, the lower the pressure it exerts
- C. pressure in liquid act only in a direction perpendicular to the sides of the containing vessel
- D. pressure is independent of the acceleration due to gravity
Which of the following units is equivalent to the watt?
- A. kgms-2
- B. kgm2s-3
- C. kgm2s-2
- D. kgm2s-1