Maharashtra Board Class 10 Science — Flashcards for Quick Revision

A: Gravitation is the universal force of attraction between any two objects in the universe. It acts between bodies on Earth and also between planets, stars, and other objects.

A: Newton concluded that Earth attracts the apple towards its centre. That is why the apple falls vertically downward, along the direction towards the centre of the Earth.

A: Centripetal force is the force that acts on an object moving in a circle and is directed towards the centre of the circle. It keeps the object in circular motion.

A: Heredity is the transfer of biological characters from one generation to another via genes. It helps offspring resemble their parents in many traits.

A: Gregor Johann Mendel is called the pioneer of modern genetics. His conclusions about heredity took a long time to be understood.

A: In 1901, the mutational theory of Hugo de Vries explained the reasons behind sudden changes. Mutation means a minor or considerable change due to a change in the position of a nucleotide in a gene.

A: Elements are classified as metals, nonmetals, and metalloids. Metals lie on the left side of the zig-zag line, nonmetals lie on the right side, and metalloids lie along the border of the zig-zag line.

A: As more elements were discovered, their properties became difficult to study one by one. Classification made it easier to study patterns and similarities among elements.

A: A triad is a group of three elements with similar chemical properties. Dobereiner showed that the atomic mass of the middle element is approximately equal to the mean of the atomic masses of the other