scientist, discoveries & inventions MCQ section 3 Practice Questions Answers Test with Solutions & More Shortcuts

Answer: (b)

A venturi meter is used to measure the flow speed of a fluid in a pipe. It is essentially a short pipe consisting of two conical parts with a short portion of the uniform cross-section in between.

It is always used in a way that the upstream part of the flow takes place through the short conical portion while the downstream part of the flow is through the long one.

Answer: (d)

An optical fibre (or optical fibre) is a flexible, transparent fibre made of glass (silica) or plastic, slightly thicker than a human hair. It functions as a waveguide, or “light pipe”, to transmit light between the two ends of the fibre.

The field of applied science and engineering concerned with the design and application of optical fibres is known as fibre optics. Optical fibres are widely used in fibre-optic communications, which permits transmission over longer distances and at higher bandwidths (data rates) than other forms of communication.

Narinder Singh Kapany (born 31 October 1926 in Moga, Punjab, India) is an Indian born American physicist who invented optical fibre.

Answer: (d)

There are different methods of counting microbial growth. These are based on different parameters of cells such as dry-weight and wet-weight measurement, absorbance, cell plate, density, turbidity, ATP measurement, viable count, ATPase activity and use of Coulter counter. Absorbance is measured by using a spectrophotometer.

Cell growth of any bacterial suspension at a particular wavelength at different intervals is measured in terms of absorbance.

Answer: (d)

Answer: (c)

Charles Babbage was an English mathematician, philosopher, inventor and mechanical engineer who originated the concept of a programmable computer. Considered a "father of the computer", Babbage is credited with inventing the first mechanical computer that eventually led to more complex designs.