Q.1:- Pure water is bad conductor of electricity because it is ?
- Feebly Ionized
- Not volatile
- A very good solvent
- A non-polar solvent
Q.2:- Lens is made up of ?
- Pyrex glass
- Flint glass
- Ordinary glass
- Cobalt glass
Q.3:- Electrostatic precipitator is used to control ?
- Air Pollution
- Water Pollution
- Solid Waste
- Noise Pollution
Q.4:- Among the following materials sound travels fastest in ?
- Steel
- Air
- Vacuum
- Water
Q.5:- The sound produced by a bat is ?
- Audible
- Subsonic
- Infrasonic
- Ultrasonic
Q.6:- The sounds having a frequency of 20 Hertz to 20,000 Hertz are known as ?
- Audible Sounds
- Ultrasonics
- Infrasonics
- Megasonics
Q.7:- Lambert’s law is related to ?
- Reflection
- Refraction
- Interference
- Illumination
Q.8:- Which type of reaction produces the most harmful radiation ?
- Fusion reaction
- Fission reaction
- Chemical reaction
- Photo-Chemical reaction
Q.9:- When hot water is sprinkled on a hotter glass tumbler, it breaks because ?
- Glass suddenly expands
- Glass suddenly contracts
- Water evaporates
- Glass reacts chemically with water
Q.10:- The velocity of sound in air ?
- Decreases with increase of temperature
- Increases with decrease of temperature
- Does not depend on temperature
- Decreases with decrease of temperature
Q.11:- A vacuum cleaner works on the principle of pressure difference. On the moon it will ?
- Work as efficiently as on the Earth
- Not work at all
- Work with reduced efficiency
- Work with increased efficiency
Q.12:- Should cars have bumpers that collapse under impact ?
- Yes, since the offending car should get damaged and pay for the mistake
- No, since it would be very expensive to get the car repaired
- No, since the colliding car would then ram into the occupants and kill them
- Yes, since they help to absorb the impact of a collision and keep the occupants safe
Q.13:- The radiant energy having lowest energy is ?
- Gamma rays
- UV rays
- Visible light
- Microwave radiation
Q.14:- The magnifying power of an astronomical telescope can be decreased by ?
- Decreasing the focal length of the eyepiece
- Increasing the focal length of the eyepiece
- Increasing the focal length of the objective
- None of these
Q.15:- The material used in the fabrication of a transistor is ?
- Aluminium
- Copper
- Silicon
- Silver
Q.16:- A person wears spectates with concave lenses. It means that normally (when not using glasses), the image of distant objects is focussed in his eyes ?
- Behind the retina
- In front of the retina
- On the retina
- On the blind spot
Q.17:- An aircraft can perform aerobatic manoeuvres in a vertical loop because of ?
- Gravity
- Centripetal Force
- Weight
- Centrifugal Force
Q.18:- Damp clothes are dried in spin dryers by the action of ?
- Centripetal forces
- Centrifugal forces
- Central forces
- Non central forces
Q.19:- The surface tension of water on adding detergent to it ?
- Increases
- Decreases
- No change
- Becomes zero
Q.20:- In sunlight a rose appears red. In green light, the same rose appears ?
- Red
- Black
- Green
- Yellow
Q.21:- Woollen cloth protects the body from cold because ?
- It is a good conductor of heat
- It is a poor conductor of heat
- External heat rays enter into the body through the woollen cloth
- It reflects heat
Q.22:- Ocean currents are an example of ?
- Convection
- Conduction
- Insulation
- Radiation
Q.23:- Which colour of light shows maximum deviation when passed through a prism ?
- Red
- Green
- Violet
- Yellow
Q.24:- Waves that are required for long distance wireless communication are ?
- Infrared rays
- Ultraviolet rays
- Radio waves
- Microwaves
Q.25:- A rear-view mirror for driving is ?
- Plain
- Concave
- Convex
- Inverted
