CBSE NCERT Class VI (6th) | Science | Physics
Chapter : Motion and Measurement of Distances
CBSE NCERT Solved Question Answer
Q1. Name few means of transport available in ancient times before the invention of wheel.
Ans 1. Boats and domestic animals.
Q2. Which invention made a great change in modes of transport
Ans2. invention of the wheel.
Q3. Name some commonly used units of measurements in ancient times.
Ans. the length of a foot, the width of a finger, and the distance of a step, a handspan and a cubit.
Q4. In taking measurement of a length using a scale, what precautions should we take?
Ans. we need to take care of the following:
1. Place the scale in contact with the object along its length as shown in Fig.10.7. NCERT
2. In some scales, the ends may be broken. You may not be able to see the zero mark clearly (Fig.10.8 (a)].
In such cases, you should avoid taking measurements from the zero mark of the scale. You can use any other full mark of the scale, say, 1.0 cm . Then you must subtract the reading of this mark from the reading at the other end.
3. Correct position of the eye is also important for taking measurement. Your eye must be exactly in front of the point where the measurement is to be taken.
Q5. How do you decide whether an object is in motion or at rest?
Ans. If a body changes its position with respect to its surroundings, it is said to be in motion, and if it does not change its position with respect to its surroundings, it is at rest.
Q6. How can we decide that how fast or slow a motion is.
Ans. Motion is a change in the position of an object with time.
The change in this position can be determined through distance measurements. This allows us to know how fast or slow a motion is.
The movement of a snail on the ground, ----SLOW An aeroplane flying high up in the air - Fast
Q7. Name the S.I. unit of length.
Ans. Metre is the unit of length in SI unit.
Q8. The ball is rolling on the ground – Name the type of motion exhibited by it.
Ans. the ball undergoes a rectilinear motion as well as rotational motion.
Q9. What do you mean by measurement?
Ans. measurement means the comparison of an unknown quantity with a known quantity.
Q10. In how many parts do we express the result of a measurement ?
Ans. The result of a measurement is expressed in two parts.
One part is a number. The other part is the unit of the measurement. For example, if in Activity 1, the length of the room is found to be 12cm. 12 is the number and cm is the unit selected for the measurement.
Q11. When is the motion of a body said to be rectilinear ,circular, periodic ?
Ans. When objects move along a straight line,the type of motion they possess is rectilinear motion.
When the distance of the object from the centre remains the same, the type of motion It possesses is circular motion.
When an object or a part of it repeats its motion after a fixed interval of time, the type of motion It possesses is periodic motion.