If a set of defective weights are used by a student to find the mass of an object using a physical balance, a large number of reading will reduce :-

Options

A. Random error
B. Systematic error
C. Random as well as systematic error
D. Neither random nor systematic error

Answer

To solve the question, we need to understand the types of errors that can occur when using a physical balance with defective weights. Here's a step-by-step breakdown:

### Step 1: Understand the Types of Errors
- **Random Errors**: These errors arise from unpredictable fluctuations in the measurement process. They can be caused by various factors such as environmental changes, slight variations in the measurement technique, or instrument sensitivity.
- **Systematic Errors**: These errors are consistent and repeatable inaccuracies that occur due to faulty equipment or incorrect calibration. They can be minimized by adjusting the measuring instrument or using calibrated weights.

### Step 2: Analyze the Impact of Defective Weights
- When defective weights are used, they introduce a consistent error in the measurements. This means that every time the student measures the mass of an object, the reading will be off by a certain amount due to the faulty weights.

### Step 3: Consider the Effect of Taking Multiple Readings
- Taking a large number of readings can help average out random errors. However, if the weights are systematically defective, the error will not change with repeated measurements. Instead, the same systematic error will persist across all readings.

### Step 4: Identify the Correct Answer
- Since the defective weights introduce a systematic error, taking multiple readings will not reduce this type of error. However, it can help reduce random errors. In this case, the question specifically asks about the effect of a large number of readings, which primarily addresses random errors.

### Conclusion
- Therefore, the correct answer is that a large number of readings will reduce **random error**.

### Final Answer
- The correct option is **A: random error**.

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