Secondary School (English Medium) (5 to 8) कक्षा ८ - CBSE Question Bank Solutions

Which among the following is considered as the cleanest fuel?

Choose the incorrect statement from the following.

A good fuel is one which

State whether the following statement is True or False.

Calorific value of wood is higher than that of coal.

Write True/False against the following statement and also correct the false statement.

Greater the calorific value, better is the fuel.

Give two examples each for a solid, liquid and gaseous fuel along with some important uses.

Although wood has a very high calorific value, we still discourage its use as a fuel. Explain.

For the metamorphosis of tadpoles which of the following elements must be available in water?

Unscramble the underlined word in the following sentence.

Reproductive life of a woman lasts from hacreemn to spauoemen.

Give a suitable word for the following statement.

It marks the beginning of reproductive period.

Two blocks of iron of different masses are kept on a cemented floor as shown in the following figure. Which one of them would require a larger force to move it from the rest position?

Will force of friction come into play when a rain drop rolls down a glass window pane?

Two boys are riding their bicycles on the same concrete road. One has new tyres on his bicycle while the other has tyres that are old and used. Which of them is more likely to skid while moving through a patch of the road which has lubricating oil spilled over it?

Figure shows two boys applying force on a box. If the magnitude of the force applied by each is equal, will the box experience any force of friction?

Cartilage is present in the joints of our body which helps in their smooth movement. With advancing age, this cartilage wears off. How would this affect the movement of joints?

Two friends are trying to push a heavy load as shown in the following figure. Suggest a way which will make this task easier for them.

When we hear a sound, does any part of our body vibrate? Name the part.

Boojho planned an activity to observe an object A through pipes as shown in the following figure so that he could see objects which he could not directly see.

1. How many mirrors should he use to see the objects?
2. Indicate the positions of the mirrors in the figure.
3. What must be the angle with respect to the incident light at which he should place the mirrors?
4. Indicate the direction of rays in the figure.
5. If any of the mirrors is removed, will he be able to see the objects?

Figure shows the word REST written in two ways in front of a mirror. Show how the word would appear in the mirror.

Explain how fertilisers are different from manure.

Describe the construction of a kaleidoscope.