Explanation

Newton's Law of Gravitation states that every particle attracts every other particle in the universe with a force

That is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

Explanation

Radioactivity was discovered by Henri Becquerel in 1896.

They discovered radioactivity proving that the uranium emitted radiation without an external source of energy such as the Sun

Marie Curie with her husband Pierre Curie, coined the term radioactivity.

In 1903, Henry Becquerel shared the Nobel Prize for Physics with Pierre and Marie Curie

Ernest Rutherford did many experiments studying the properties of radioactive decay (alpha, beta, and gamma)

Explanation

Alfred Nobel was a chemist from Sweden. 

Dynamite was invented by Alfred Nobel in the 1860s.

He is also the founder of the Nobel Prize

He also invented Nitro-glycerine in 1875.

Alfred Nobel  Born: October 21, 1833, Stockholm, Sweden

Alfred Nobel  Died: on December 10, 1896, in Sanremo, Italy

Alfred Nobel Full name: Alfred Bernhard Nobel

Additional Information

The first Noble Prize was awarded on 10th December 1901

The first Noble Prize was awarded in Stockholm, Sweden.

Explanation

The Wright Brothers, Orville and Wilbur, invented and flew the first successful airplane.

This historic flight took place on December 17, 1903, in Kitty Hawk, North Carolina.

Explanation

• Carbon dioxide (CO2) is a major greenhouse gas.
• It responsible for about 65% of the Earth's greenhouse effect.

Explanation

Opaque objects form sharp and dark shadows because they block all light from passing through, creating a clear and defined shadow.

Explanation

Melting of ice changes only the state from solid to liquid.

No new substance is formed, so it's a physical and reversible change.

Explanation

A nutcracker works as a lever to multiply force.

It helps crack hard nuts with less effort.

Explanation

Temporary hardness of water is caused by dissolved bicarbonates of calcium and magnesium.

It can be removed by boiling, which decomposes Ca(HCO₃)₂ into insoluble carbonate.

Explanation

Plaster of Paris changes into gypsum on mixing with water 

It is commonly called P.O.P. is calcium sulfate hemihydrate.

The chemical formula of plaster of Paris  is CaSO4.1/2 H2O

Crystals of gypsum are produced when Plaster of Paris is mixed with water 

Gypsum is calcium sulfate dihydrate and a mineral used in cement manufacturing.

It helps in controlling the rate of hardening of the cement.