Some Natural Phenomena — Science STD 8 — Question

Name four combinations of two metals each that can be used in a Voltaic cell.

What is the difference between weight and mass?

Name an additional feature of a plant cell.

How does the greenhouse effect differ on Earth compared to Venus?

Which of the following are oviparous animals and which are viviparous animals? Frog, Human being, Sparrow, Lizard, Cow, Dog, hen, Fish, Butterfly, Cat.

Leguminous plants do not require nitrogenous fertilisers. Why Is It so ?

Name two events (other than earthquakes) which can cause tremors on the earth.

An archer stretches her bow while taking aim at the target. She then releases the arrow, which begins to move towards the target. Based on this information, fill up the gaps in the following statements using the following terms: muscular, contact, non-contact, gravity, friction, shape, attraction
(a) To stretch the bow, the archer applies a force that causes a change in its ____________ .
(b) The force applied by the archer to stretch the bow is an example of ____________ force.
(c) The type of responsible for a change in the state of motion of the arrow is an example of a ____________ force.
(d) While the arrow moves towards its target, the forces acting on it are due to ____________ and that due to ____________ of air.

Explain in brief about the celestial objects. Also, mention the name of any two celestial objects.