Please provide a rating, it takes seconds and helps us to keep this resource free for all to use
Welcome to our Physics lesson on Linear Momentum as a Quantity that Represents the Amount of Motion for an Object, this is the first lesson of our suite of physics lessons covering the topic of Linear Momentum, you can find links to the other lessons within this tutorial and access additional physics learning resources below this lesson.
By definition, Linear Momentum (p⃗) is the product of an object's mass (m) and its velocity (v⃗).
Mathematically, we have
Since mass is measured in kg and velocity in m/s, the unit of momentum is [kg × m/s].
It is obvious that momentum is a vector quantity as it is obtained through the multiplication of a vector (velocity) by a scalar (mass). As stated in the tutorial "Multiplication of a Vector by a Scalar", the result is a new vector, which is collinear with the original one.
A 300 t asteroid is moving in space at 5 km/s towards the Earth. What is its momentum in kg × m/s?
First, we must convert the units into the basic ones. Thus, since 1 t = 1000 kg and 1 km = 1000 m, we have
Therefore, we obtain for the momentum of the asteroid:
Thus, we say the momentum of the asteroid is 1.5 × 109 kg × m/s towards the Earth.
In the past, momentum has been known as the "amount of motion." This term is logical because a very large momentum as the one obtained in the example above, means the object's motion is very big. As a result, the object may cause a lot of harm when hitting another body, such as the Earth. On the other hand, a very light object (such as the tennis ball in the Introduction paragraph) which moves slowly has a small amount of motion, as its momentum is small.
In the next paragraph, it will be clearer why momentum has been called "amount of motion" in the past.
You have reached the end of Physics lesson 6.5.1 Linear Momentum as a Quantity that Represents the Amount of Motion for an Object. There are 2 lessons in this physics tutorial covering Linear Momentum, you can access all the lessons from this tutorial below.
Enjoy the "Linear Momentum as a Quantity that Represents the Amount of Motion for an Object" physics lesson? People who liked the "Linear Momentum lesson found the following resources useful:
Please provide a rating, it takes seconds and helps us to keep this resource free for all to use
We hope you found this Physics lesson "Linear Momentum" useful. If you did it would be great if you could spare the time to rate this physics lesson (simply click on the number of stars that match your assessment of this physics learning aide) and/or share on social media, this helps us identify popular tutorials and calculators and expand our free learning resources to support our users around the world have free access to expand their knowledge of physics and other disciplines.