CBSE Class-7 Science: Questions 249 - 254 of 322

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Question number: 249

» Wastewater Story » Waste Water Treatment Plant » Sludge

MCQ▾

Question

Processes of sludge treatment are:

Choices

Choice (4) Response
a.

Solid Composting, Incinerating

b.

Incinerating, Dewatering, solid composting

c.

Dewatering, Solid composting

d. All a. , b. and c. are correct

Question number: 250

» Electric Current and Its Effects » Electromagnet » Electric Bell

MCQ▾

Question

Springy metal strip in an electric bell is used to:

Choices

Choice (4) Response
a.

Produce sound

b.

Adjust the contact between metal strip and mains

c.

Making and breaking the contacts

d. Question does not provide sufficient data or is vague

Question number: 251

» Wastewater Story » Sanitation and Disease » Sanitation at Public Places

MCQ▾

Question

The practice of open defecation leads to:

Choices

Choice (4) Response
a.

Contamination of sources of underground water like wells, tubewells

b.

Soil Contamination

c.

Contamination of water tables

d. All a. , b. and c. are correct

Question number: 252

» Electric Current and Its Effects » Magnetic Effect of Electric Current » Compass

MCQ▾

Question

Needle of a compass always points towards the:

Choices

Choice (4) Response
a.

South-North direction

b.

North-South direction

c.

South-South direction

d.

North-North direction

Question number: 253

» Wastewater Story » Sewage » Sewers and Sewerages

MCQ▾

Question

The underground pipes, which carry away, dirty drainage water and waste matter from the house is called as:

Choices

Choice (4) Response
a.

Sewer

b.

Sewerage

c.

Gutter

d. Both a. and c. are correct

Question number: 254

» Electric Current and Its Effects » Electromagnet » What Are Electromagnets

MCQ▾

Question

Electromagnets are used in:

Choices

Choice (4) Response
a.

Used in industry and municipalities

b.

Modern electrical devices

c.

For separating iron from non-magnetic materials

d. All a. , b. and c. are correct

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