Problem 12-12: Engineering Mechanics- Dynamics (Hibbeler 14th Edition)

Rectilinear Kinematics with Constant Acceleration

This lesson applies the constant-acceleration kinematic equations to find the time and distance required for a car to change speed along a straight road. Students learn to select the appropriate equation for each unknown and verify results using an independent check equation.

Question:
A car traveling with an initial speed of 70 kilometers per hour accelerates at a constant rate of 6000 kilometers per hour squared along a straight road. First, how long will it take the car to reach a speed of 120 kilometers per hour? Second, through what distance does the car travel during this time?

In this lesson, you will learn to:
• Identify the appropriate constant-acceleration kinematic equation based on the given and unknown quantities
• Solve for elapsed time using the velocity–time equation $v = v_0 + at$
• Solve for displacement using the vel