# Constant Acceleration: find time

• Akar
In summary, the problem states that a man driving a car at 78 km/h sees a deer at a distance of 101m. The question is how much time is needed for the car to slow down after driving 99m and stop, with the equation Δx = 1/2 (vi + vf) * t to be used. The person trying to solve the problem is unsure of how to find Δx, but it is given that the car drove 99m before stopping.
Akar

## Homework Statement

A man was driving a car at 78 km/h, he saw a deer at the distance of 101m, how much time is needed so that the car slows down after it drove 99m and stops.

## Homework Equations

Δx = 1/2 (vi + vf) * t​

## The Attempt at a Solution

I'm thinking about finding the Δx

Akar said:
I'm thinking about finding the Δx
not sure I understand. Are you saying you do not know how to determine Δx? It is given.

Akar said:

## Homework Statement

A man was driving a car at 78 km/h, he saw a deer at the distance of 101m, how much time is needed so that the car slows down after it drove 99m and stops.

## Homework Equations

Δx = 1/2 (vi + vf) * t​

## The Attempt at a Solution

I'm thinking about finding the Δx
Aren't you given the Δx? How far did the car drive until it stopped?

Edit: Oops! @haruspex got there before me!

## 1. What is constant acceleration?

Constant acceleration is the rate of change of velocity over time that remains steady. This means that the velocity of an object increases by the same amount in each unit of time.

## 2. How do you calculate time with constant acceleration?

To calculate time with constant acceleration, you can use the formula t = (vf - vi)/a, where t is time, vf is final velocity, vi is initial velocity, and a is acceleration.

## 3. Can constant acceleration be negative?

Yes, constant acceleration can be negative. This indicates that the object is decelerating, or slowing down, at a constant rate.

## 4. How does constant acceleration affect an object's motion?

Constant acceleration causes an object's velocity to change at a constant rate, resulting in a linear change in its position over time. This means that the object's motion is uniform and predictable.

## 5. What are some real-life examples of constant acceleration?

Some real-life examples of constant acceleration include a car gradually speeding up or slowing down on a straight road, a roller coaster going down a hill, and a ball falling due to gravity.

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