Exam Started

1. An electric bulb is labeled 260V, 80W. How much current is taken by the bulb?

A. 0.46A B. 0.82A C. 0.4A D. 0.31A

2. What is the effect of using split−rings in a simple d.c. generator?

A. The direction of rotation of the coil is reversed B. The current in the coil flows in the same direction C. The current in the coil flows in the same direction the current in the coil becomes alternating D. The contact with the voltage source is cut off

3. One of the conditions necessary for an object to be in equilibrium when acted upon by a number of parallel forces is that the vector sum of the forces is

A. Average B. Zero C. Negative D. Positive

4. The fundamental frequency of an open organ pipe is the same as that of the second overtone of a closed organ pipe of length 0.2m. What is the length of the open organ pipe?

A. 0.132m B. 0.160m C. 0.125m D. 0.080m

5. Frictional force is an advantage in which of the following situations?

A. Stopping a car suddenly B. Holding an object firmly C. Sliding down a slide D. Walking on a slippery floor

6. Which of the following remains unchanged when light travels from one medium to another?

A. Frequency B. Velocity C. Wavelength D. None

7. I. It decreases when contaminant is added to a liquid
II. It increases when contaminant is added to a liquid
III. It decreases with increase in temperature
Which of the above is/are correct about surface tension?

A. I and II B. II and III C. I only D. I and III

8. A given barometric altimeter reads zero Pascal

A. In the atmosphere B. In the sea C. On land D. In outer space

9. Semiconductor is a class of solid whose conductivity increases with an increase in _____

A. Pressure B. Temperature C. Current D. Voltage

10. Petrol produces a cooling effect when it is poured on the hand because it has _____

A. Low conductivity B. High conductivity C. High latent heat of vaporization D. Low latent heat of vaporization

11. The area under a force - distance curve is _____

A. Work B. Impulse C. Pressure D. Momentum

12. Under what conditions are cathode rays produced in a discharge tube?

A. High pressure and low voltage B. High pressure and high voltage C. Low pressure and low voltage D. Low pressure and high voltage

13. Which of the following is a scalar quantity?

A. Moment B. Momentum C. Potential energy D. Acceleration

14. Shadows and eclipse result from the

A. Reflection of light B. Rectilinear propagation of light C. Diffraction of light D. Refraction of light

15. A bifocal lens can be used to correct which type of defect?

A. Short-sightedness B. Astigmatism C. Long-sightedness D. Presbyopia

16. Two long parallel wires carry equal currents in opposite directions. The magnetic field at a point midway between the wires will:

A. be zero B. be directed perpendicular to the plane containing the wires C. be equal to the sum of the fields due to each wire D. depend on the square of the distance between the wires

17. Calculate the electric field intensity between two plates of potential difference 6.5V when separated by a distance of 35cm

A. 18.57NC⁻¹ B. 53.06NC⁻¹ C. 2.28NC⁻¹ D. 0.80NC⁻¹

18. The focal length of a concave mirror is 2.0cm. if an object is placed 8.0cm from it, the image is at

A. 2.7cm B. 2.0cm C. 2.3cm D. 2.5cm

19. Which of the following statement is correct?

A. Pressure exerted is higher with a narrow heel shoe than a flat heel shoe B. No pressure is exerted in both narrow and flat heel shoes C. Pressure exerted is lower with a narrow heel shoe than a flat heel shoe D. Pressure exerted is the same in both narrow and flat heel shoes

20. A coil is rotated in a uniform magnetic field. Which of the following increases the maximum induced EMF in the coil?

A. Decreasing the number of turns B. Increasing the speed of rotation C. Rotating the coil slower D. Using thinner wire

Physics