3rd Class Computers Science Growth of Modern Computer The Second Generation Computers (1956-65)                

The Second Generation Computers (1956-65)

In 1947, three scientists, John Bardeen, William Shockley and Walter Brattain working at AT&T's Bell Labs invented the transistor which functioned like a vacuum tube. The transistor was faster, more reliable, smaller and much cheaper to build than a vacuum tube. One transistor replaced the equivalent of 40 vacuum tubes. The use of this machine marked a new beginning for the computer. The development of the transistor was soon applied to computers which reduced their size, the power requirement and increased their processing speed. Some models of the second generation computers are IBM 1401, IBM 1620, IBM 7094 and UNIVAC 1108. IBM-700, 1401 and ATLAS. (See Figure 3.2.4)

The main feature of the second generation computers was that the computers of this generation replaced vacuum tubes with transistors. Magnetic cores and different magnetic storage devices for storage were invented in this generation. Eighty percent of these computers were used in business and industries of the commercial applications developed during this period. (See Figure 3.2.5)

• Limitations:

After removing the limitations of 1st generation computers, 2nd generation computers were developed. Despite that, it had many limitations.

• Few of them are the following:
• The major drawback was that the computers of the second generation produced some amount of heat.
• They had slow speed.
• They had less memory.

Therefore, 3rd generation computers were developed with more advanced technology.

 Different models of 1st generation computer and 2nd generation computer are given. Match the following:

                A                                             B

        1. 1^st Generation                               i. UNIVAC-1108 

                                                                    ii. ENIAC

       2. 2^nd Generation                               iii. ENIAC-101

                                                                    iv. ATLAS

                                                                    v.   IBM 1401

(A) 1- v, iii; 2- i, iv                                             

(B) 1- ii, iii; 2- iv, v

(C) 1-i, ii, iii; 2-iv, v                                           

(D) 1-ii; 2-i,iv, v

(E) 1- iv; 2- ii, tii, iv

Answer: (D)

Explanation

Correct Option:

(D) Option (D) is matched correctly. Incorrect Options:

(A) Option (A) is matched incorrectly

(B) Option (B) is matched incorrectly

(C) Option (C) is matched incorrectly

(E) Option (E) is matched incorrectly

 To overcome the drawbacks of 1st generation computer, 2nd generation computers were developed. But it had few limitations as well. Which of the following are the limitations of 2nd generation computer?

1. These computers had slow operating speed and small computing capacity.
2. They had slow speed.
3. They had high memory.
4. Second generation computer produced some amount of heat.

(A) 1 and 2                                                         

(B) 2, 3 and 4

(C) 2 and 4                                                                          

(D) All of these

(E) None of these

Answer: (C)

Explanation

Correct Option:

(C) Statements 2 and 4 are the limitations of 2nd generation computers. Incorrect Options:

(A) Statement 1 is the limitation of 1st generation computer and statement 2 is the limitation of 2nd generation computer. Therefore, option (A) is incorrect.

(B) Statements 2 and 4 are the limitations of 2nd generation computers but statement 4 is an incorrect statement. Therefore, option (B) is incorrect.

(D) All the given statements are not the limitations of 2nd generation computers. Therefore, option (D) is incorrect.

(E) Option (E) is incorrect.