Class 9 Science Tissues: NCERT Solutions for Question 2

Diagrammatically show the difference between the three types of muscle fibres.

What does a neuron look like?

Draw a labelled diagram of a neuron.

Complete the table:

Give three features of cardiac muscles.

What are the functions of the stomata?

How many types of elements together make up the xylem tissue? Name them.

What is a tissue?

Differentiate between striated, unstriated and cardiac muscles on the basis of their structure and site/location in the body.

What are the constituents of phloem?

Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?

State the universal law of gravitation.

Which of the following are matter?

Chair, air, love, smell, hate, almonds, thought, cold, cold-drink, smell of perfume.

A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (Fig. 11.3). Let us take it that the force acts on the object through the displacement. What is the work done in this case?

What is meant by a pure substance?

How does the sound produced by a vibrating object in a medium reach your ear?

In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium observations are in agreement with the law of conservation of mass.

sodium carbonate + ethanoic acid → sodium ethanoate + carbon dioxide + water

What are canal rays?

State any two conditions essential for good health.

How is our atmosphere different from the atmospheres on Venus and Mars?

If number of electrons in an atom is 8 and number of protons is also 8, then (i) what is the atomic number of the atom? and (ii) what is the charge on the atom?

A freely falling object eventually stops on reaching the ground. What happenes to its kinetic energy?

Fig 8.11 shows the distance-time graph of three objects A,B and C. Study the graph and answer the following questions:

          Fig. 8.11

(a) Which of the three is travelling the fastest?
(b) Are all three ever at the same point on the road?
(c) How far has C travelled when B passes A?
(d) How far has B travelled by the time it passes C?

Explain how bats use ultrasound to catch a prey.

Hydrogen and oxygen combine in the ratio of 1:8 by mass to form water. What mass of oxygen gas would be required to react completely with 3 g of hydrogen gas?

From a rifle of mass 4 kg, a bullet of mass 50 g is fired with an initial velocity of 35 m s^-1. Calculate the initial recoil velocity of the rifle.

What is the nature of the distance-time graphs for uniform and non-uniform motion of an object?

A person has a hearing range from 20 Hz to 20 kHz. What are the typical wavelengths of sound waves in air corresponding to these two frequencies? Take the speed of sound in air as 344 m s^-1.

A 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track. If the engine exerts a force of 40000 N and the track offers a friction force of 5000 N, then calculate:

(a) the net accelerating force;
(b) the acceleration of the train; and
(c) the force of wagon 1 on wagon 2.

Calculate the molecular masses of H₂, O₂, Cl₂, CO₂, CH₄, C₂H₆, C₂H₄, NH₃, CH₃OH.