Sound — Science STD 9 — Question

Name the superclass of Chordata in which lateral line sense organs are found.

Name the tissue and write characteristic feature of following. Connects bone to bone in humans.

Name the region of the atmosphere where most of the atmospheric gases are present.

What is the difference between infrasonic waves and ultrasonic waves?

Suppose a ball of mass m is thrown vertically upward with an initial speed v, its speed decreases continuously till it becomes zero. Thereafter, the ball begins to fall downward and attains the speed v again before striking the ground. It implies that the magnitude of initial and final momentums of the ball are same. Yet, it is not an example of conservation of momentum. Explain why?

Define relative density. What is the SI unit of relative density?

Define a mixture. Give two points of evidence to show that sugar solution is a mixture.

Rivers from land add minerals to sea water. Discuss how?