To get an image, larger than object, one can use

• Convex mirror
• Concave mirror
• Plane mirror
• Plano Convex mirror
Correct Option: B  [ Concave mirror ]

Remark:

Dialysis is prescribed for patients having:

• Liver disease
• Lung trouble
• Kidney trouble
• Heart Disease
Correct Option: C  [ Kidney trouble ]

Remark:

Bluetooth is a technology in communication which features

• wireless communication using radio waves
• wireless communication using infrared rays
• wireless communication using microwaves
• wireless communication using laser
Correct Option: A  [ wireless communication using radio waves ]

Remark: Bluetooth is a wireless technology using radio frequencies to share data over a short distance.

In a forest ecosystem, green plants are

• the primary producers.
• the secondary consumers.
• the decomposers.
• both secondary consumers and decomposers.
Correct Option: A  [ the primary producers. ]

Remark: The green plant in the ecosystem are called producers. In a terrestrial ecosystem, major producers are herbaceous and woody plants. Likewise, producers in an aquatic ecosystem are various species like phytoplankton, algae and higher plants.

Helium is preferred to hydrogen in air balloons because it:

• is cheaper
• is less dense
• has greater lifting power
• does not form an explosive mixture with air
Correct Option: D  [ does not form an explosive mixture with air ]

Remark:

The red planet is

• Venus
• Saturn
• Mars
• Neptune
Correct Option: C  [ Mars ]

Remark:

Magnification produced by a rear view mirror fitted in vehicles:

• is less than the object
• is more than the object
• is equal to the object
• can be more or less than the object depending upon the position of object in front of it.
Correct Option: A  [ is less than the object ]

Remark:

The mountaineers carry oxygen with them because:

• at an altitude of more than 5 km there is no air
• the amount of air available to a person on mountain is lesser than that available on the ground
• the temperature of air is lesser than that on the ground.
• The pressure of air is higher than that on the ground.
Correct Option: B  [ the amount of air available to a person on mountain is lesser than that available on the ground ]

Remark:

Lens is made up of:

• pyrex glass
• flint glass
• ordinary glass
• cobalt glass
Correct Option: B  [ flint glass ]

Remark:

The only snake that builds its nest is:

• Krait
• King cobra
• Chain viper
• Saw scaled viper
Correct Option: B  [ King cobra ]

Remark: