Explanation

Alexander Graham Bell is often credited with being the inventor of the telephone since he was awarded the first successful patent. 

Telephone was invented in 1876.

Graham Bell made the first-ever telephone call to his partner, Thomas Watson.

Explanation

Penicillin was discovered by Alexander Flaming In 1928.

Penicillin was the first true antibiotic.

The first patient Albert Alexander, a 43-year-old policeman, was treated with penicillin on 12 February 1941.

Alexander Flaming determined that penicillin had an antibacterial effect and published his findings in 1929.

Explanation

Colour of the plants is green due to the presence of Chlorophyll۔

Chlorophyll absorbs certain wavelengths of light within the visible light spectrum.

Chlorophyll is the green color pigment which absorbs wavelength from sunlight.

Since the synthesis of food occurs in the presence of sunlight, it is called photosynthesis. 

Explanation

The neutron is a neutral particle,

which is stable only in the confines of the nucleus of the atom.

Explanation

All plants move Anticlockwise around Sun.

All plants move anticlockwise around their axis.

Earth rotates its axis from West to East.

Explanation

When the soap is in the form of micelles then it has the ability to clean the oily dirt which gets accumulated at the centre.

These micelles remain as colloidal solutions.

Therefore, the dirt from the cloth is easily washed away.

Explanation

In the early 1950s, the first successful vaccine was created by US physician Jonas Salk.

Salk tested his experimental killed-virus vaccine on himself and his family in 1953

First used Salk vaccine in 1955 ( in activated)

while 

A live attenuated (weakened) oral polio vaccine developed by Dr. Albert Sabin and first used in 1961.

Israel launched a polio vaccine drive after 1988 in April 2022.

Explanation

Explanation

For water, the boiling point is 100ºC at a pressure of 1 atm

The boiling point of water decreases at higher altitudes due to Low atmospheric pressure

The boiling point of water increases with increased atmospheric pressure

The boiling point of water decreases with decreased atmospheric pressure

ND17-1-2023

Explanation

The SI unit of pressure is Pascal (represented as Pa) 

in SI base units, one kilogram per meter per second squared (N/m2 or kg m-1s-2)

Definition of Pressure: Pressure can be defined as the force acting per unit area.

***

The SI unit of energy/work is the joule (J)

ND23-9-2023