Extra 30 short questions and answers from the chapter:10 "Motion and Measurement of Distances" for Class 6 Science (CBSE):
Why do we need standard units of measurement?
Answer:
Earlier, people used non-standard units like handspan and footstep, which varied from person to person.
To avoid confusion, standard units like meters and
centimetres
were introduced for accuracy.
What are the SI units of length and time?
Answer:
The SI unit of length is
meter (m)
.
The SI unit of time is
second (s)
.
Define motion.
Answer:
Motion is the change in position of an object with respect to time.
What is measurement?
Answer:
Measurement is the process of comparing an unknown quantity with a known standard unit.
Why was there a need to develop standard units of measurement?
Answer:
Different people used different units, causing confusion.
Standard units provide accuracy and uniformity worldwide.
What are some ancient methods of measurement?
Answer:
Handspan:
Distance between the tip of the thumb and the little finger.
Cubit:
Distance from the elbow to the tip of the middle finger.
Footstep:
Length of a single step.
What is the main disadvantage of using non-standard units for measurement?
Answer:
Non-standard units like handspan and cubit vary from person to person, leading to inaccurate measurements.
What is the correct way to use a ruler for measuring length?
Answer:
The ruler should be placed along the object.
The eye should be exactly above the point to avoid errors.
What precautions should be taken while measuring a length using a ruler?
Answer:
Place the ruler along the object.
Start measuring from zero.
Keep the eye directly above the scale.
What are the different devices used for measuring length?
Answer:
Scale (Ruler)
– Used for small objects.
Measuring tape
– Used for longer distances.
Vernier
callipers
– Used for precise small measurements.
What is rectilinear motion? Give an example.
Answer:
Motion in a straight line is called
rectilinear motion
.
Example: A car moving on a straight road.
What is circular motion? Give an example.
Answer:
Motion along a circular path is called
circular motion
.
Example: The hands of a clock.
What is periodic motion? Give an example.
Answer:
Motion that repeats after a fixed time interval is called
periodic motion
.
Example: A swinging pendulum.
What is rotational motion? Give an example.
Answer:
When an object spins around a fixed point or axis, it is called
rotational motion
.
Example: A spinning top.
Give an example of an object showing both rectilinear and rotational motion.
Answer:
A
moving bicycle
shows
rectilinear motion
(when moving forward) and
rotational motion
(wheels spinning).
What type of motion does the Earth show?
Answer:
The Earth
rotates on its axis
(rotational motion).
The Earth
revolves around the Sun
(circular motion).
How is circular motion different from rectilinear motion?
Answer:
Rectilinear motion
occurs in a straight line (e.g., a car on a straight road).
Circular motion
occurs along a curved path (e.g., the motion of a fan blade).
What type of motion does a ceiling fan show?
Answer:
A
ceiling fan
shows
rotational motion
as it spins around its axis.
What type of motion does a pendulum have?
Answer:
A pendulum shows
periodic motion
as it swings back and forth at regular intervals.
What kind of motion does a rolling ball exhibit?
Answer:
A rolling ball shows
both rectilinear and rotational motion
.
What are the different types of motion?
Answer:
Rectilinear motion
Circular motion
Periodic motion
Rotational motion
What kind of motion does a bouncing ball exhibit?
Answer:
A bouncing ball shows
periodic motion
and
rectilinear motion
.
What is the standard unit of measurement? Why is it important?
Answer:
The standard unit of measurement is the
meter
.
It ensures uniformity and accuracy in measurements.
What is the difference between measurement and estimation?
Answer:
Measurement
gives an exact value using instruments (e.g., a ruler).
Estimation
gives an approximate value without measuring tools.
What is the full form of SI?
Answer:
SI
stands for
International System of Units
.
How can we measure the length of a curved line?
Answer:
Use a
thread
to trace the curved line and then measure the length of the thread using a ruler.
How do we measure large distances like the distance between two cities?
Answer:
Large distances are measured in
kilometres
(km)
using
odometers
in vehicles or maps.
Give an example where an object shows more than one type of motion.
Answer:
A
wheel of a moving car
shows
rotational motion
(spinning) and
rectilinear motion
(moving forward).
Why do we need different types of motion classification?
Answer:
Objects move in different ways, and classification helps us understand and study them better.
Why is it necessary to measure distances accurately?
Answer:
Accurate measurements are important in daily life, science, and engineering to ensure correctness and precision.
