An artificial satellite of Earth nears the end of its life due to air resistance. While still in orbit:

Options

A. It moves faster as the orbit lower
B. It moves slower as the orbit lowers
C. It slowly spirals away from Earth
D. It moves slower in the same orbit but with a decreasing period

Explanation

To solve the question regarding the behavior of an artificial satellite nearing the end of its life due to air resistance while still in orbit, we can analyze the situation step by step.

### Step-by-Step Solution:

1. **Understanding the Scenario**:
- An artificial satellite is in orbit around the Earth and is experiencing air resistance. This air resistance will affect its motion.

2. **Effect of Air Resistance**:
- As the satellite moves through the atmosphere, air resistance acts against its motion, causing it to lose altitude. This means the satellite will gradually spiral downwards towards Earth.

3. **Conservation of Mechanical Energy**:
- The mechanical energy of the satellite is the sum of its potential energy (due to its height above the Earth) and its kinetic energy (due to its speed). According to the conservation of energy, if the satellite loses potential energy (as it descends), its kinetic energy must increase to keep the total mechanical energy constant.

4. **Potential Energy Decrease**:
- As the satellite descends, its height decreases, leading to a decrease in potential energy. This is given by the formula \( PE = mgh \), where \( m \) is mass, \( g \) is the acceleration due to gravity, and \( h \) is the height.

5. **Kinetic Energy Increase**:
- To maintain the conservation of mechanical energy, the decrease in potential energy must be compensated by an increase in kinetic energy. This is represented by the formula \( KE = \frac{1}{2}mv^2 \), where \( v \) is the velocity of the satellite.

6. **Conclusion about Velocity**:
- Since the kinetic energy increases as the satellite descends, the velocity of the satellite must also increase. Therefore, as the orbit lowers, the satellite moves faster.

7. **Choosing the Correct Option**:
- Based on the analysis, the correct answer is that the satellite "moves faster as the orbit lowers."

### Final Answer:
The correct option is: **A) It moves faster as the orbit lowers.**