A composite solid propellant is `:`

Options

A. `N_(2)O_(4)+` acryclic rubber
B. `N_(2)O_(4)+` monomethylhydrazine `(M MH)`
C. Polyurethane `+` ammonium perchloride
D. Nirocellulose `+` nitroglycerine

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Composite Solid Propellant:**
A composite solid propellant is a type of propellant used in rocketry and other applications that combines various components to achieve desired performance characteristics.

2. **Composition:**
In a composite solid propellant, the ingredients are physically mixed. This means that the components do not chemically react with each other but are combined to form a heterogeneous mixture.

3. **Physical Structure:**
The physical structure of a composite solid propellant is heterogeneous, meaning that it has distinct phases or components that can be identified separately.

4. **Components:**
The primary components of a composite solid propellant include:
- **Oxidizers:** These are substances that provide oxygen to support the combustion of the fuel. In composite solid propellants, crystalline particles often act as oxidizers.
- **Fuels:** Organic plastic fuels serve as binders that hold the oxidizer particles together. Common examples of these fuels include polyurethane and polybutadiene.

5. **Examples:**
Specific examples of materials used in composite solid propellants include:
- **Polyurethane:** A type of polymer that acts as a binder and fuel.
- **Ammonium Perchlorate:** A common oxidizer used in solid propellants.

6. **Conclusion:**
Therefore, a composite solid propellant is characterized by its heterogeneous mixture of oxidizers and fuels, which are physically mixed to create a solid propellant that can be used effectively in various applications.

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