Question Discussion & Solution

The correct answer is Electric Heater.

Key Points

• Electric Heater is a device that can convert Electric energy into heat energy.
• In an electron tube, an electric heating element shaped in the form of a wire or ribbon is used to supply heat to a cathode; the element provides heat when a current is passed through it.
• Electric heaters also are used for domestic central heating and for materials processing in the industry for example heat pumps; electric furnace.

Additional Information

• Energy is the ability to do work.
• The  Law of conservation of energy:
  • Energy can neither be created nor be destroyed, only Energy can be converted from one form to another.
• These are some parts of the energy that convert one form to another:
  • Heat
  • Light
  • Motion
  • Electrical
  • Chemical
  • Gravitational

Important Points

The correct answer is option 4.

Explanation:

• Compact Disc-Recordable (CD-R) technology is known as Write Once-Read Many (WORM), which allows you to write data onto a disk just once that can not be erased.
• CD-R discs are blank CDs that can record data written by a CD burner. After that, the data is permanent and can be read any number of times. ​

Additional Information

• The data burned onto a CD-R disc is permanent.

• CD-RW Stands for "Compact Disc Re-Writable."
  • A CD-RW is a blank CD that can be written to by a CD burner. 
  • CD-RW can be written multiple times.
• CD-ROM Stands for "Compact Disc Read-Only Memory."
  • A CD-ROM is a CD that can be read by a computer with an optical drive. 

• ​Another term of Worm (termed as 'malware') A computer worm is a malicious virus, that is a self-replicating software program that affects the functions of hardware and software programs.​​

1^st letter: increase by - 8, - 4, - 2, - 1

P - 8→ H - 4→ D - 2 → B - 1 → A

2^nd letter: second letter increase by + 2

K + 2→ M +2 → O + 2 → Q + 2 → S

3^rd letter: Decrease by - 1

R - 1→ Q – 1 → P - 1 → O – 1 → N

The correct answer is Silicon.

• An integrated circuit, or IC, is a small chip that can function as an amplifier, oscillator, timer, microprocessor, or even computer memory.
• An IC is a small wafer, usually made of silicon, that can hold anywhere from hundreds to millions of transistors, resistors, and capacitors.
• An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small flat piece (or "chip") of semiconductor material that is normally silicon.

Key Points

• Silicon is a highly pure, easy to use, and cheap semiconductor, perfect for the now huge computer chip industry.
• Silicon is used because it can be used as either an insulator (doesn't allow electricity to flow) or a semiconductor (allows a little flow of electricity).

Important Points

The advantages of ICs :

• Extremely small in size.
• Low power consumption.
• Reliability.
• Reduced cost.
• Very small weight.
• Easy replacement. 

Here the pattern is,

4320 ÷ 6 = 720,

720 ÷ 5 = 144,

144 ÷ 4 = 36,

36 ÷ 3 = 12,

12 ÷ 2 = 6