Olympiad Test Level 2: Science and Technology - 2 - Class 4 MCQ

IOS and Android are System Software. These are designed to run computer's hardware and process programs. They are built in the system. Youtube and Google Chrome are application software. These are applications which are used by any user based on his/her requirements.

John Logie Baird invented first television. On 26 January, 1926, he first gave the public demonstration of the machine which he called as “televisor”.

Steam Engine was invented by James Watt. Steam engine is an engine that works by taking power from the steam. However, steam engines have direct effect on the environment as they cause air pollution by release of carbon dioxide.

• Statement I is incorrect because application software typically requires a human interface to interact with the user. It does not run on its own without user input or interaction.
• Statement II is correct because an operating system is indeed a type of system software that manages hardware and provides services for application software.

In 1853, American inventor Elisha Otis demonstrated a freight elevator equipped with a safety device to prevent falling in case a supporting cable should break. This increased public confidence in such devices. Otis established a company for manufacturing elevators and patented (1861) a steam elevator.
Many people think that he invented the elevator, but the truth is, he invented the elevator brake. He also invented the railway safety brake.

Electric battery was invented by Alessandro Volta. An electric battery is a device which is used to give power to electrical devices. X-rays were invented by Roentgen. X-rays are used to examine various parts of the body. Printing Machine was invented by Johannes Gutenberg. With this invention it was possible to print large number of books. Barometer was invented by Evangelista Torricelli. Barometer is a device which is used to measure atmospheric pressure.

A pulley is classified as a simple machine because it consists of a wheel on an axle or shaft that is designed to support movement and change the direction of force.

A flagpole typically has a pulley. A pulley is used to raise and lower the flag easily by using a rope that runs over a wheel, making it simpler to manage the flag without climbing the pole.

Carbon-monoxide is emitted from the exhaust pipe of the vehicles by the combustion of fuels. It is a poisonous gas.

Ice is solid at 0⁰C, but when it is kept at room temperature, the temperature increases, therefore, it becomes liquid.