Units And Measurement

To find the difference between one main scale division and one vernier scale division, we use the formula:

Substituting the given values:

Therefore, the least count of the microscope is: 0.0102 mm.

Since the options are provided in different units, we can convert this to centimeters:

The correct answer is: (A) 0.01 mm.

Given:

• True length of the wire: 3.678 cm
• Measured length using instrument A: 3.5 cm
• Measured length using instrument B: 3.38 cm

Step 1: Understanding Accuracy and Precision

• Accuracy: How close the measurement is to the actual value.
• Precision: How close repeated measurements are to each other.

Step 2: Comparing Measurements

Accuracy is determined by comparing the measured value to 3.678 cm:

• Error in A:
• Error in B:

Since 3.5 cm is closer to 3.678 cm than 3.38 cm, instrument A is more accurate.

Precision is determined by the number of significant figures:

• Instrument A measures up to 2 decimal places.
• Instrument B measures up to 3 decimal places, implying higher precision.

Step 3: Conclusion

The measurement with A is more accurate, while measurement with B is more precise.

Answer: The correct option is A.