Math Problem Statement

A race car has a speed of 98 m/s. The driver hits the breaks causing the car to slow down at a constant rate of 12 m/s^2 for a period of 8 seconds. Compute the distance traveled by the car at 2s, 4s, 6s, and 8s.

Solution

To solve this problem, we need to compute the distance traveled by the race car at 2 seconds, 4 seconds, 6 seconds, and 8 seconds, under constant deceleration.

Given:

  • Initial velocity (v0v_0): 98 m/s
  • Deceleration (aa): 12 m/s² (since it's slowing down, this value is negative in the equations)
  • Time intervals: 2 seconds, 4 seconds, 6 seconds, and 8 seconds

We will use the equation of motion:

d(t)=v0t+12at2d(t) = v_0 t + \frac{1}{2} a t^2

where:

  • d(t)d(t) is the distance traveled at time tt,
  • v0v_0 is the initial velocity,
  • aa is the acceleration (which will be negative in this case because the car is decelerating),
  • tt is the time.

Step-by-step calculation:

  1. At t=2t = 2 seconds: d(2)=98×2+12×(12)×(2)2d(2) = 98 \times 2 + \frac{1}{2} \times (-12) \times (2)^2

  2. At t=4t = 4 seconds: d(4)=98×4+12×(12)×(4)2d(4) = 98 \times 4 + \frac{1}{2} \times (-12) \times (4)^2

  3. At t=6t = 6 seconds: d(6)=98×6+12×(12)×(6)2d(6) = 98 \times 6 + \frac{1}{2} \times (-12) \times (6)^2

  4. At t=8t = 8 seconds: d(8)=98×8+12×(12)×(8)2d(8) = 98 \times 8 + \frac{1}{2} \times (-12) \times (8)^2

Now, let's compute these distances.The distances traveled by the race car at the specified times are:

  1. At t=2t = 2 seconds, the car travels 172 meters.
  2. At t=4t = 4 seconds, the car travels 296 meters.
  3. At t=6t = 6 seconds, the car travels 372 meters.
  4. At t=8t = 8 seconds, the car travels 400 meters.

Would you like further details or explanations?

Here are 5 related questions for further practice:

  1. What is the final velocity of the car at t=8t = 8 seconds?
  2. How much distance does the car travel in the first second?
  3. If the car continued to decelerate, when would it come to a complete stop?
  4. What would the distance be if the deceleration was 10 m/s² instead of 12 m/s²?
  5. How much time would it take to stop the car completely?

Tip: The equation of motion d(t)=v0t+12at2d(t) = v_0 t + \frac{1}{2} a t^2 is very useful for problems involving uniformly accelerated motion, even when acceleration is negative (deceleration).

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Kinematics
Uniformly Accelerated Motion
Deceleration

Formulas

d(t) = v_0 * t + 0.5 * a * t^2

Theorems

Equations of Motion

Suitable Grade Level

Grades 9-12