Understanding Semiconductors

Which of the following devices is mentioned as being powered by semiconductors?

• Smartphone

• Refrigerator

• Washing machine

• Television remote

What is the main characteristic of a semiconductor in terms of electrical conductivity?

• It blocks electrical flow completely

• It allows free electron flow

• It has controllable conductivity

• It conducts electricity better than metals

Why are semiconductors ideal for controlling electrical signals in complex circuits?

• Their conductivity is too high

• Their conductivity is too low

• Their conductivity can be precisely controlled and manipulated

• They block electrical flow completely

In the Bohr model, where are electrons located in an atom?

• Orbiting in discrete shells around the nucleus

• Fixed inside the nucleus

• Randomly scattered outside the atom

• Shared between atoms in a molecule

Which energy band contains electrons that are bound to atoms?

• Valence band

• Conduction band

• Forbidden band

• Excited band

What are intrinsic semiconductors?

• Pure semiconductors that barely conduct electricity at room temperature

• Semiconductors with high conductivity due to impurities

• Semiconductors made only from metals

• Semiconductors that conduct electricity very well at all temperatures

Why is precise control over conductivity through doping important in electronics?

• It allows engineers to build diodes, transistors, and integrated circuits

• It makes semiconductors completely non-conductive

• It increases the melting point of semiconductors

• It reduces the cost of semiconductor materials

Which of the following is a primary function of photovoltaic devices in solar cells?

• Convert sunlight directly into electricity

• Store electrical energy for later use

• Amplify electrical signals

• Emit visible light

According to the material, what is a significant impact of the semiconductor revolution on human civilization?

• It has transformed civilization more profoundly in 70 years than any other technology in history

• It has made all mechanical devices obsolete

• It has eliminated the need for renewable energy

• It has reduced the need for communication systems

Why are billions of transistors packed into chips smaller than a fingernail important for modern technology?

• They power computers and smartphones

• They generate solar energy

• They provide wireless internet

• They store mechanical energy