9. SAMPLE PROBLEM
Jenny accelerates at
45 m/s2 with in 120
seconds. Find the
velocity?
Given:
a= 45 m/s2
v= ?
t= 120s
Solution:
v = at
v = (45 m/s2)(120s)
v = 5,400m/s
Editor's Notes
After determining “how far the object moves?”, the next question will be “How fast did the object move?” This information can be provided by the object’s speed or velocity.
Having a uniform velocity while traveling is impossible to achieve. As we enter a road with heavy traffic, our vehicle slows down. Then after passing that crowded street, we speed up. There is a change in velocity. This change in velocity in a particular time interval is called accelartion.
Having a uniform velocity while traveling is impossible to achieve. As we enter a road with heavy traffic, our vehicle slows down. Then after passing that crowded street, we speed up. There is a change in velocity. This change in velocity in a particular time interval is called accelartion.
Acceleration does not only refer to speeding up but also to slowing down.
For instance, a car is traveling north at a speed of 30 km/h, then turns right at corner while maintaining its speed. The speed of the car is uniform at 30 km/h but the velocity changes because its direction changes from north to east.
Since the velocity is increasing or decreasing uniformly with time, we can express the average velocity as the arithmetic average of the initial and final velocity.