Important Questions for HSC Science (Electronics) 12th Board Exam - Maharashtra State Board

Define terms: Fuel cell

Write the chemical equations involved in the following reactions:(i) Hoffmann-bromamide degradation reaction

Write the chemical equations involved in the following reactions:(i) Hoffmann-bromamide degradation reaction

Features of Monopolistic Competition.

Features of Monopolistic Competition.

Features of Monopolistic Competition.

State Ampere’s circuital law

Explain the law of demand with its assumptions.

Explain the law of demand with its assumptions.

Explain the law of demand with its assumptions.

The following data were obtained during the first order thermal decomposition of SO₂Cl₂ at a constant volume :

SO₂Cl₂ (g) → SO₂ (g) + Cl₂ (g)

Calculate the rate constant.

(Given : log 4 = 0.6021, log 2 = 0.3010)

Account for the following : Nitrogen does not form pentahalide.

Distinguish between the following.

Micro Economics and Macro Economics.

Derive the mathematical expression for law of radioactive decay for a sample of a radioactive nucleus

Derive the mathematical expression for law of radioactive decay for a sample of a radioactive nucleus

State Henry’s law.

Explain the term Antiseptics

Answer the following question.
Explain the secondary functions of money.

(A) Read the following extract and answer the questions given below:
   Chronic floods during the monsoon, on average, affect more than 30 million Indians annually Ironically, 60% of India's farmland, 66% of its livestock and its entire forest area depend on rains for survival.
   According to a recently released Central Water Commission (CWC) report, on an average, 7·21 million hectares (roughly 72,000 sq. km.) go under floodwater. This water typically ravages 3·78 million hectares of agricultural land, damaging crops worth Rs. 1, 118 crores annually.
   Heavy rains and floods account for nearly 1,700 lives lost annually. Apart from this, I ·25 lakh houses are annually damaged by torrential rains that also wipe out nearly 96,000 livestock.
   Floods are the most recurrent natural calamity, hitting India almost every year. According to the CWC's report on financial aspects of flood control, anti-sea erosion and drainage projects, it is not possible to provide absolute protection instantly to all flood-prone areas. It says that such an attempt will neither be practical nor economically viable.
   The CWC's analysis of floods in India from 1953 to 2011 shows a marginal decline in flood-affected areas over the years, the data shows 1977 1978 and 1979 were the worst-hit. The 1977 floods killed over 11,000 people, six-time the average for the 59 years, between 1953 and 2011. In terms of area and population affected, the floods of 1978 were the most destructive.
  In terms off the financial loss, recent floods have been far more destructive. The total loss of crops, houses and public utilities in 2009 was Rs. 32541 crores, the highest for any year.

Question
(1) What is the above extract about?

(2) How do floods adversely affect India?

(3) Why is it not possible to provide absolute protection to all flood-prone areas?

(4) How would you help the flood-affected people?

(5) Rewrite the following sentences in the ways instructed :
(i) The floods of 1978 were the most destructive.
(Change the sentence into the 'positive degree'.)
(ii) Floods are the most recurrent natural calamity hitting India almost every year.
(Make it a complex sentence.)
(iii) Floods have been far more destructive.
(Rewrite the sentence using the Simple Present tense.)

(6) Give the meanings of:
(i) entire
(ii) calamity

(B) Write a brief summary of the above extract with the help of the points given below and suggest a suitable title.
Floods - natural, recurrent calamity in India - destroy life and property - no absolute protection - neither practical nor economically viable- floods in 1977 and 1978. 

Describe, with the help of a circuit diagram, the working of Zener diode as a voltage regulator.