The velocity of a particle measured from an instrument is 0.00204300 `m//s`. The number of significant figures is

Options

A. 8
B. 4
C. 6
D. 3

Answer

To determine the number of significant figures in the given measurement of velocity, we can follow these steps:

### Step 1: Identify the number
The given velocity is 0.00204300 m/s.

### Step 2: Identify leading zeros
Leading zeros (the zeros before the first non-zero digit) are not significant. In this case, the leading zeros are "0.00" in 0.00204300.

### Step 3: Count non-zero digits
The non-zero digits in the measurement are "2", "4", and "3". Each of these digits is significant.

### Step 4: Identify and count trailing zeros
Trailing zeros (the zeros after the last non-zero digit) in a decimal number are significant. In this case, the trailing zeros are "00" after "3".

### Step 5: Total count of significant figures
Now, we can count all the significant figures:
- Non-zero digits: 2, 4, 3 (3 significant figures)
- Trailing zeros: 00 (2 significant figures)

Adding these together gives us:
3 (from 2, 4, 3) + 2 (from trailing zeros) = 5 significant figures.

### Conclusion
The total number of significant figures in the measurement 0.00204300 m/s is **6**.

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