In order to stop a car in shortest distance on a horizontal road one should

Options

A. apply the brakes very hard so that the wheels stop rotating
B. apply the brakes heard enough to just prevent slipping
C. pump the brakes (press and relese)
D. shut the engine of and not apply brakes

Answer

To solve the question "In order to stop a car in shortest distance on a horizontal road one should," we can follow these steps:

### Step 1: Understand the Concept of Friction
Friction is the force that opposes the relative motion of two surfaces in contact. There are two types of friction relevant here: static friction and kinetic friction. Static friction acts when the surfaces are not slipping, while kinetic friction acts when they are sliding past each other.

**Hint:** Remember that static friction is generally greater than kinetic friction, which is crucial for stopping the car effectively.

### Step 2: Identify the Goal
The goal is to stop the car in the shortest distance possible. To achieve this, we need to maximize the frictional force acting on the tires without causing them to skid.

**Hint:** Think about how frictional force can be maximized while ensuring the tires maintain grip on the road.

### Step 3: Apply the Brakes
When applying the brakes, we want to ensure that the tires are not slipping. This means we need to apply the brakes hard enough to utilize the maximum static friction force, which is the limiting friction.

**Hint:** Consider the relationship between the force applied and the type of friction that is in play.

### Step 4: Determine the Condition for Maximum Stopping Force
To stop the car in the shortest distance, the tires should be on the verge of slipping. This means that the static friction is at its maximum value, which is equal to the limiting friction.

**Hint:** Reflect on the importance of the tires maintaining contact with the road surface to utilize static friction effectively.

### Step 5: Choose the Correct Option
From the options provided, the correct choice would be to "apply the brakes hard enough to just prevent slipping." This ensures that the car stops in the shortest distance by maximizing the frictional force.

**Hint:** Look for the option that emphasizes maintaining grip while applying maximum braking force.

### Final Answer
To stop a car in the shortest distance on a horizontal road, one should apply the brakes hard enough to just prevent slipping.