Measurement of Length and Motion MCQs for UPSC Prelims

Why is it useful to estimate a length before measuring it?

1. A A measured value far from the estimate warns you that something has gone wrong
2. B Estimating removes the need to measure at all
3. C Estimating tells you what material the object is made of
4. D An estimate is always more accurate than a measurement

Which of these units gives the same answer no matter who does the measuring?

1. A Metre
2. B Footstep
3. C Cubit
4. D Handspan

How many centimetres make up $1\ \text{m}$?

1. A $100\ \text{cm}$
2. B $1000\ \text{cm}$
3. C $10\ \text{cm}$
4. D $60\ \text{cm}$

In circular motion, which of these stays the same?

1. A The position of the object
2. B The distance of the object from the centre
3. C The length of the path already covered
4. D The direction in which the object is moving

To measure a curved line with a thread, what is the correct order of steps?

1. A Wrap the thread around the ruler and count the number of turns
2. B Cut the thread into small pieces and count how many there are
3. C Straighten the thread on a ruler first, then lay it along the curve
4. D Lay the thread along the curve, mark the two ends, then straighten the thread on a ruler

Why must the thread be laid along the curve without stretching it?

1. A A stretched thread becomes shorter, so the measured length comes out too small
2. B Stretching the thread makes it harder to read on a ruler
3. C A stretched thread becomes longer, so the measured length comes out too large
4. D Stretching the thread changes the shape of the curve