# Car Deceleration Problem

A car is travelling at a steady speed of 90 km/h when an emergency occurs. The driver carries out a panic-braking stop, locking all the wheels (no ABS!).

a. Derive expressions for the deceleration under the following conditions:

i. if the car is ascending a slope of angle Q from the horizontal

ii. if it is on a horizontal road surface

iii. if it is descending the slope.

b. Assuming that the weather is dry, the slope is designated as 10% and the mass of the car, M, is 950 kg, determine for the three cases described in part (a) the decelerations and the time taken for the car to come to rest.

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#### Solution Preview

Thank you, for providing the friction factor. The solution of the problem is attached in a word file.

Car dynamics

Problem Statement

A car is travelling at a steady speed of 90 km h−1 when an emergency occurs. The driver carries out a panic-braking stop, locking all the wheels (no ABS!).

1. Derive expressions for the deceleration under the following conditions:

a. if the car is ascending a slope of angle Q from the horizontal

b. if it is on a horizontal road surface

c. if it is descending the slope.

2. Assuming that the weather is dry, the slope is designated as 10% and the mass of the car, M, is 950 kg, determine for the three cases described in part (a) the decelerations and the time taken for the car to come to rest.

Fundamentals Used

Force due to gravity: Force due to gravity always acts vertically down on any mass M. This force can be ...

#### Solution Summary

This solution helps with a car deceleration problem.