Ropes made of nylon and polyester are commonly used in cranes and elevators because

Options

A. Nylon is inflammable
B. It is a good conductor of heat and electricity
C. It is very strong, fairly elastic and light weight
D. It is heat resistant

Answer

**Step-by-Step Solution:**

1. **Identify the Materials**: The question mentions that ropes are made of nylon and polyester.

2. **Understand the Properties of Nylon and Polyester**: Both nylon and polyester are synthetic fibers known for their specific properties.

3. **Evaluate the Options**: The question provides several options regarding the properties of these materials. We need to determine which property makes them suitable for use in cranes and elevators.

4. **Analyze the Properties**:
- **Inflammable**: This is not a desirable property for ropes used in cranes and elevators.
- **Good conductor of heat and electricity**: This is also not a desirable property for ropes, as they should ideally be insulators.
- **Strong, fairly elastic, and lightweight**: This is a desirable property. Ropes need to be strong to support heavy loads, elastic to absorb shocks, and lightweight for ease of handling.
- **Heat resistant**: While this is a useful property, it does not directly relate to the primary reasons for using nylon and polyester in ropes.

5. **Conclusion**: The correct answer is that nylon and polyester fibers are strong, fairly elastic, and lightweight, which makes them suitable for use in cranes and elevators.

**Final Answer**: Ropes made of nylon and polyester are commonly used in cranes and elevators because they are strong, fairly elastic, and lightweight.

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