Step 1:

Initial speed of auto mobile is .

Human reaction time is sec.

Acceleration is .

.

First law of motion: .

Substitute and   in the formula.

When the auto mobile is stopped, .

sec.

Step 2:

Find the distance traveled by the auto mobile, when sec.

Second law of motion: ..

Substitute , and in the formula.

.

Find the distance covered during reaction time. 

.

Find stopping distance by adding results in (1) and (2).

Stopping distace is .

Solution:

Stopping distace is .

Step 1:

Initial speed of auto mobile is .

Human reaction time is sec.

Acceleration is .

.

First law of motion: .

Substitute and   in the formula.

When the auto mobile is stopped, .

sec.

Step 2:

Find the distance traveled by the auto mobile, when sec.

From Linear motion equation : .

Substitute , and in the formula.

.

Find the distance covered during reaction time. 

.

Find stopping distance by adding results in (1) and (2).

Stopping distace is .

Solution:

Stopping distace is .