The apparent weight of a man in a moving lift is less than his real weight when it is going down with

 

(A) retardation

 

(B) linear momentum

 

(C) uniform speed

 

(D) an acceleration

Energy may be defined as

(A) capacity of doing work

(B) rate of doing work

(C) power of doing work

(D) all the above

The unit of force in C.G.S. system of units is called

(A) kg

(B) dyne

(C) newton

(D) all the above

Ground water is usually free from

(A) dissolved impurities

(B) suspended impurities

(C) both suspended and dissolved impurities

(D) none of the above

The suitable method for disinfection of swimming pool water is

(A) chlorination

(B) by using potassium permanganate

(C) ultra violet rays treatment

(D) lime treatment

Which one of the following would contain water with the maximum amount of turbidity?

(A) wells

(B) rivers

(C) oceans

(D) lakes

The rainfall at any place may be determined by

(A) its intensity

(B) its frequency

(C) its direction

(D) all the above

A garden developed over top of surface water tank is known as

(A) water tank garden

(B) hanging garden

(C) municipal garden

(D) none of these

Temporary hardness in water is caused by the presence of

(A) chlorides of Ca and Mg

(B) bicarbonate of Ca and Mg

(C) sulphates of Ca and Mg

(D) nitrates of Ca and Mg

Bacteria that need oxygen to live are known as

(A) pathogenic bacteria

(B) facultative bacteria

(C) anaerobic bacteria

(D) aerobic bacteria

Suspended impurities in water is

(A) algae

(B) bacteria

(C) silts

(D) all of these