Dimensional formula for curie is

Options

A. `[M° L T^(–1)]`
B. `[M° L^(–1) T°]`
C. `[M° L° T^(–1)]`
D. `[M^(–1) L° T°]`

Explanation

To find the dimensional formula for Curie, we need to understand what Curie represents in terms of physical quantities.

### Step-by-Step Solution:

1. **Understanding Curie**:
- Curie (Ci) is a unit of radioactivity that represents the number of radioactive nuclei decaying per second.
- Mathematically, it can be expressed as the rate of decay of radioactive nuclei.

2. **Expression for Curie**:
- The expression for Curie can be written as:
\[ \text{Curie} = \frac{dN}{dt} \]
- Here, \( dN \) is the change in the number of radioactive nuclei, and \( dt \) is the change in time.

3. **Analyzing the Components**:
- \( dN \) represents the number of nuclei, which is a count and thus dimensionless. Therefore, it has no dimensions:
\[ [dN] = M^0 L^0 T^0 \]
- \( dt \) represents time, which has the dimension:
\[ [dt] = M^0 L^0 T^1 \]

4. **Finding the Dimensional Formula**:
- Now, we can find the dimensional formula for Curie by dividing the dimensions of \( dN \) by the dimensions of \( dt \):
\[ [\text{Curie}] = \frac{[dN]}{[dt]} = \frac{M^0 L^0 T^0}{M^0 L^0 T^1} = M^0 L^0 T^{-1} \]

5. **Final Result**:
- Therefore, the dimensional formula for Curie is:
\[ [\text{Curie}] = M^0 L^0 T^{-1} \]

### Conclusion:
The dimensional formula for Curie is \( M^0 L^0 T^{-1} \).