Class 6 Science Chapter 7 MCQ

Here, are all the statements are correct. Hence, your answer will be option [D].

The distance between Delhi and Mumbai is expressed in kilometer because other units like meter, centimeter and decameter are so small to express this big distance.

Here, are all the statements are incorrect. Hence, your answer will be option [D]. In option [A]: If an object moves fairly fast, then its movement or motion can be observed easily. In option [B]: If an object moves very slowly, then it becomes very difficult to observe its movement immediately. In option [C]: When an object is stationary it is said to be at rest.

Time of the first bell in the school does not express a time interval because it has only a single value of time, while the other quantities like a day, a second and a school period can be divided into a number of shorter periods of time. Note: A time interval should have at least two values of time.

We have to convert the height of 1.56 m into mm. Now, we know that: 1 meter = 1000 mm So, 1.56 m = 1000 x 1.56 mm = 1560 mm Thus, a height of 1.56 m is equal to 1560 millimeter

When an object turns or spins about a fixed axis, it is called rotational motion. When an object moves along a straight-line path it is called rectilinear motion. When a bicycle moves on a straight road, turning of bicycle wheel shows the rotational motion. And as it goes in a straight road, it exhibits the rectilinear motion.

Since, ribbon is folded 5 times, Length of ribbon = (27.5 – 2) cm x 5 = (25.5 x 5) cm = 127.5 cm = 1.27 m 1.27 m lies in the range of 1.25 m – 1.35 m.

The thickness of a coin or a thin wire is a very small length which is much smaller than even centimeter. So, it is inconvenient to express very small length in terms of centimeters. Thus, to express the thickness of a coin or a thin wire we use millimeter as the unit of length. The very small length is expressed in still smaller units called a “millimeters”.

Here, are all the statements are correct. Hence, your answer will be option [D].

A communication satellite is stationed in an orbit high above the earth which shows three types of motion rotational motion, periodic motion and circular motion but not exhibit rectilinear motion.

Here, are all the statements are correct. Hence, your answer will be option [D].

When a ball is moving on the ground, it is rotating as well as moving forward on the ground. So, a ball rolling on the ground has two types of motion, rotational motion as well as a rectilinear motion.

Motion of an object or a part of it around a fixed point is known as circular motion. Note: In circular motion an object moves such that its distance from a fixed point remains the same.

If we consider a merry-go-round as a whole, then it shows rotational motion because it turns on an axle. But the outer part of merry-go-round (on which children sit) shows circular motion. So, a merry-go-round has two types of motion at the same time, rotational motion and circular motion.

In ancient times, people used boats for transport along water routes such as rivers or any water sources. Initially the boats were simple logs of wood in which a hollow cavity was made for people to sit and carry goods.

Here, are all the statements are correct. Hence, your answer will be option [D].

All the reasons are correct. Hence, your answer will be option [D].

Here, are all the statements are correct. Hence, your answer will be option [D].

The earth moves around the sun, so it has circular motion. The earth repeats its motion around the sun after regular intervals of time, so it has periodic motion and the earth rotates on its axis, so it has also rotational motion. Thus, the earth has three types of motion at the same time: circular motion, periodic motion and rotational motion.

In the beginning of 19th century, the invention of steam engine introduced a new source of power to run transport vehicles. Steam engines were used to pull trains on railroads or railway tracks for carrying people and goods from one place to another. Steam engines were also used to run ships in the beginning. The steam engine is called external combustion engine because the fuel or coal for making steam was burnt outside the engine.

The scientist all over the world have adopted “International System” of units or SI units which have a uniformity in the measurement of various physical quantities like length, mass and time etc. The SI unit of measuring length is “meter”. The symbol of meter is “m”. The SI unit of measuring mass is “kilogram” (kg) and the SI unit of measuring time is “second” (s)

The screw undergoes two kinds of motion that is periodic motions and circular motion.

Here, all the statements are correct. Hence, your answer will be option [D].

Here, all the statements are correct. Hence, your answer will be option [D].

The process of finding an unknown quantity by comparing it with a known fixed quantity of the same kind, called measurement. And unit of measurement accepted universally, called the standard unit. But when we guess the amount of anything without actual measurement, called “Estimation”.