An example where the speed of the object increases, then remains constant for some time, and then decreases is a car driving on a straight road. Here is a step-by-step breakdown of what happens:
The car starts from rest and begins to accelerate, increasing its speed.
After some time, the car reaches a constant speed and maintains it for a while.
As the car approaches a red light or a stop sign, the driver applies the brakes, causing the car to decelerate and slow down.
This example demonstrates how an object can experience both acceleration and deceleration over a period of time. The car's acceleration causes its speed to increase, while its deceleration causes its speed to decrease.
This example also highlights the importance of understanding acceleration and deceleration in real-world situations. By understanding how acceleration and deceleration work, drivers can operate their vehicles more safely and efficiently, and engineers can design better transportation systems.