1 dyne cm= ........

Options

A. 1 erg
B. 1 newton cm
C. 10 newton cm
D. none of these

Explanation

To solve the question "1 dyne cm = ........", we need to understand the relationship between dyne cm and the unit of work in the CGS (centimeter-gram-second) system.

### Step-by-Step Solution:

1. **Identify the Units**:
- Dyne is a unit of force in the CGS system.
- Centimeter (cm) is a unit of length in the CGS system.
- When we multiply force (in dynes) by distance (in centimeters), we get work.

2. **Understand the Concept of Work**:
- Work is defined as the product of force and displacement.
- In the CGS system, the unit of work is called "erg".

3. **Relate Dyne cm to Erg**:
- 1 dyne cm is equivalent to 1 erg because:
- Work (in ergs) = Force (in dynes) × Distance (in centimeters).
- Therefore, 1 dyne × 1 cm = 1 erg.

4. **Convert Erg to Other Units**:
- We know that 1 erg is also equal to 1 x 10^-7 joules in the SI system.
- However, since the question asks for the relationship in CGS units, we focus on the erg.

5. **Final Conclusion**:
- Since 1 dyne cm = 1 erg, and we also know that 1 erg is equal to 1 arc (as both are units of work in the CGS system), we can conclude:
- 1 dyne cm = 1 arc.

### Answer:
1 dyne cm = 1 arc.