A car is travelling at constant speed along a road, and drives onto a large patch of oil. The driver applies the brakes to stop the car. Compare to braking on a dry road, what may happen?

Options

A. The car slows down more quickly because of the reduced friction between the tyres and the road.
B. The car speeds up because of the reduced friction between the tyres and the road.
C. The car takes longer time to slow down because of the reduced friction between the tyres and the road.
D. The car takes longer time to slow down because of the greater friction between the tyres and the road.

Explanation

To analyze the situation of a car braking on a dry road versus a patch of oil, we can break it down into several steps:

### Step-by-Step Solution:

1. **Understanding Braking on a Dry Road:**
- When a car is traveling on a dry road and the brakes are applied, the friction between the tires and the road surface is relatively high. This friction force is what allows the car to decelerate and eventually stop.

2. **Friction Force:**
- The friction force is crucial in stopping the car. It is determined by the coefficient of friction between the tires and the road surface. On a dry road, this coefficient is high, allowing for effective braking.

3. **Transition to the Oil Patch:**
- When the car drives onto a large patch of oil, the surface becomes slippery. The oil reduces the coefficient of friction significantly compared to the dry road.

4. **Effect of Reduced Friction:**
- With the oil present, when the driver applies the brakes, the friction force acting on the tires is greatly reduced. As a result, the tires may not grip the road effectively.

5. **Sliding Instead of Stopping:**
- Instead of decelerating quickly, the car will start to slide on the oil. This is because the friction force is not sufficient to overcome the car's momentum. The car will continue to move forward even with the brakes applied.

6. **Increased Stopping Distance:**
- Due to the reduced friction, the stopping distance will be much greater on the oil patch compared to the dry road. The car will take longer to come to a complete stop.

7. **Conclusion:**
- In summary, braking on a patch of oil will result in a longer stopping distance and a higher likelihood of losing control compared to braking on a dry road, where the friction is sufficient to stop the vehicle effectively.