IIT JEE Practice Question and Answer
8Q: The probability that a number selected at random from the first 100 natural numbers is a composite number is ? 1774 05b5cc6e3e4d2b4197774ec8e
5b5cc6e3e4d2b4197774ec8e- 13/2true
- 22/3false
- 31/2false
- 434/7false
- Show AnswerHide Answer
- Workspace
- SingleChoice
Answer : 1. "3/2"
Explanation :
Answer: A) 3/2 Explanation: The number of exhaustive events = 100 C₁ = 100. We have 25 primes from 1 to 100. Number of favourable cases are 75. Required probability = 75/50 = 3/2.
Q: Who invented Bifocal Lens? 1774 05b5cc6b9e4d2b4197774d6d5
5b5cc6b9e4d2b4197774d6d5- 1John Adamsfalse
- 2Benjamin Franklintrue
- 3James Madisonfalse
- 4Thomas Jeffersonfalse
- Show AnswerHide Answer
- Workspace
- SingleChoice
Answer : 2. "Benjamin Franklin"
Explanation :
Answer: B) Benjamin Franklin Explanation: Benjamin Franklin has long been credited with the invention of bifocal lenses and he was the first to wear bifocal lenses. He did not produce them himself but instead had some optician in London or France make them for him to overcome Presbyopia, a condition that Franklin suffered. He was tired switching between lenses for far and near sightedness. And that resulted in inventing Bifocal Lenses.
Q: How many feet are in a meter? 1774 05b5cc6bae4d2b4197774d7d5
5b5cc6bae4d2b4197774d7d5- 13.214false
- 23.28084true
- 33.2516false
- 43.21456false
- Show AnswerHide Answer
- Workspace
- SingleChoice
Answer : 2. "3.28084"
Explanation :
Answer: B) 3.28084 Explanation: We know that, 1 meter = 100 cms. => 1 meter = 3.28084 feet.
Q: Which planet has the lowest density? 1773 05b5cc69de4d2b4197774c933
5b5cc69de4d2b4197774c933- 1Earthfalse
- 2Jupiterfalse
- 3Saturntrue
- 4Neptunefalse
- Show AnswerHide Answer
- Workspace
- SingleChoice
Answer : 3. "Saturn"
Explanation :
Answer: C) Saturn Explanation: Saturn, the solar system's second largest planet that takes the prize for least dense. It's less dense than water, which has led many people to postulate that it would float. However, even if it somehow found its way to a body of water large and deep enough to contain it, Saturn would break apart and its rocky core would sink.
Q: Name the company that has recently created the world’s smallest magnet using a single atom which can store one bit of data on it. 1773 05b5cc71be4d2b4197774f553
5b5cc71be4d2b4197774f553- 1TCSfalse
- 2Microsoftfalse
- 3IBMtrue
- 4Infosysfalse
- Show AnswerHide Answer
- Workspace
- SingleChoice
Answer : 3. "IBM"
Explanation :
Answer: C) IBM Explanation: A team of researchers at IBM has created the world’s smallest magnet using a single atom which can store one bit of data on it.
Q: Metals are good conductors of electricity because 1773 05b5cc6a5e4d2b4197774ccd6
5b5cc6a5e4d2b4197774ccd6- 1The atoms are lightly packedfalse
- 2They contain free electronstrue
- 3They have high melting pointfalse
- 4All the abovefalse
- Show AnswerHide Answer
- Workspace
- SingleChoice
Answer : 2. "They contain free electrons"
Explanation :
Answer: B) They contain free electrons Explanation: Metal particles are held together by strong metallic bonds, which is why they have high melting and boiling points. The free electrons in metals can move through the metal, allowing metals to conduct electricity. Because the electrons in the atom's higher energy levels can separate from the atoms easily, they can be pulled out with very little energy. Because the molecular structure of the metal is such that 'free electrons' are free to move, thus being categorized as electrically conductive. For example, copper is used for electrical wiring because it is a good conductor of electricity.
Q: Fog is an example of a 1773 05b5cc6b8e4d2b4197774d684
5b5cc6b8e4d2b4197774d684- 1liquid dispersed in gastrue
- 2solid dispersed in liquidfalse
- 3liquid dispersed in solidfalse
- 4gas dispersed in liquidfalse
- Show AnswerHide Answer
- Workspace
- SingleChoice
Answer : 1. "liquid dispersed in gas"
Explanation :
Answer: A) liquid dispersed in gas Explanation: Fog is an example of a colloidal system liquid dispersed in gas.
Q: Wild animals are not considered a natural resource. 1772 05b5cc695e4d2b4197774c520
5b5cc695e4d2b4197774c520- 1TRUEfalse
- 2FALSEtrue
- Show AnswerHide Answer
- Workspace
- SingleChoice
Answer : 2. "FALSE"
Explanation :
Answer: B) FALSE Explanation: The given statement is False. Wild animals are considered as a natural resource. Natural resources are resources taken from nature to satisfy our needs. These natural resources are: 1) Air 2) Water 3) Soil 4) Plants 5) Animals 6) Minerals 7) Forests 8) Natural Gas 9) Coal 10) Petroleum.

