THEORY PART OF NEWTONS LAWS

1. Newton’s Laws of
Motion
LESSON BY:
NKOSI MME 215002449

2. Newton’s Laws of Motion
 Newton’s 1st Law of Motion( Law of Inertia).
Newton’s 2nd Law of Motion( Fnet=ma).
Newton’s 3rd Law of Motion( Action-Reaction Law).

3. Word from the presenter.
Many people have this paradigm that science is not real, however I do not
blame them. If something is taught but not made relevant to your everyday life,
you will believe that it is non-real.
This lesson seeks to relate science into your everyday life and bring the
awareness that science is real and is applicable in our everyday life. Let us learn
together, and explore the wonders of this world.
Enjoy the lesson.

4. Newton’s 1st Law of Motion
-An object in no motion will remain in no motion, and an object in motion will
continue to be in motion at a constant velocity, unless an unbalanced force acts
on it.
What does this Law means?
-It simply means if you were to roll a tennis ball in a flat surface it should
continue moving at a constant velocity and never stops, unless an outside
unbalanced force acts on it. And if the same tennis ball was stationary it should
remain stationary forever, unless an unbalanced force acts on it.

5. What is
Inertia
It is said to be the tendency of an
object or a body to resist changes in
its velocity, whether that object is in
motion or motionless.

6. Continuing……

7. Continuing……
The ball on the previous slide will
remain stationary forever, unless
someone comes and kick it.
Furthermore, if it was in motion it will
continue to move at a constant
velocity, unless an unbalanced force
acts on it or it is stopped by a net.

8. Continuing……
Why then do we observe everyday
objects in motion slowing down and be
at rest?
-It is because of the force of friction.
-Every object on planet Earth is under
the influence of friction.

9. Then what is Friction?

10. Continuing……

11. Newton’s 2nd
Law of
Motion
-The acceleration of an object as
produced by a net force is directly
proportional to the magnitude of the
net force, and inversely proportional to
the mass of that object.
What does that really mean?
-It means that the acceleration of an
object depends on the net force acting
on that object. For instance, If you
were to push a desk, if you apply more
force the desk will accelerate more and
if you apply less force the desk will
accelerate less. So, the higher the
force, the higher the acceleration.

12. Continuing…..

13. Mathematical
representation…
𝐹𝑛𝑒𝑡 = 𝑚𝑎
Fnet→ total forces acting on that object,
measured in Newtons(N)
m→ mass of an object, measured in kg
a→ acceleration of an object, measured in
m/s2

14. Continuing…..
Newton’s 2nd Law proves that different masses accelerate to the earth
at the same rate, but with different forces.
• We know that objects with different masses
accelerate to the ground at the same rate.
• However, because of the 2nd Law we know
that they don’t hit the
ground with the same
Force.

15. Classwork
1. What acceleration will result when
a 12 N net force applied to a 3 kg
object? A 6 kg object?
2. A net force of 16 N causes a mass
to accelerate at a rate of 5 m/s2.
Determine the mass.
3. How much force is needed to
accelerate a 66 kg skier 1 m/s2?
4. What is the force on a 1000 kg
elevator that is falling freely at 9.8
m/s2?

16. Newton’s 3rd
Law of Motion
In simpler terms Newtons 3rd
Law states that for every
cation there is an equal
opposite reaction. For
instance if you punch a wall,
it simultaneously hit back
with the same force you
applied.

17. Continuing…..

18. Continuing…..

19. The End
Hopefully you enjoyed the lesson. Thank you for your
time. Looking forward to meet you in the following
lesson.

20. REFERENCES
Judan M.D(2016), L5-Newton’s Laws of Motion. Available from Slide Share at
https://www.slideshare.net/judan1970/unit-6-lesson-65-newtons-laws-of-motion?qid=59b199f7-
d667-4e30-9275-cecc3687e52a&v=&b=&from_search=2 ( Accessed 17 August 2020)
Logos Academy(2010) Newton’s Laws of Motion. Available from Slide Share at
https://www.slideshare.net/logosacademyeduec/newtons-laws-of-motion-5224731?qid=af83492e-
9dd7-413a-9508-b1c2034d8959&v=&b=&from_search=1 ( Accessed 17 August 2020)
Anderson I(2013), Objects in Motion-04Newton’s Laws of Motion. Available from
Slide Share at https://www.slideshare.net/portlester/newtons-laws-of-motion-
25267224?qid=08d1f0ca-7bd9-4e8d-8335-a6cefe4fadd6&v=&b=&from_search=5 ( Accessed 17
August 2020)

21. REFERENCES
Smith L(2014)Chapter 2: The Laws of Motion. Available from Slides Share at
https://www.slideshare.net/LauraSmith15/force-powerpoint ( Accessed 17 August 2020)
Boggio K(2015) Newton’s Three Laws of Motion. Available from Slides at
https://www.slideshare.net/KimBoggio/laws-of-motion-46672628?qid=0a48b6f2-f15b-4b1e-
8c74-8533a1180af3&v=&b=&from_search=8 ( Accessed 17 August 2020)

22. Your best quote that reflects your
approach… “It’s one small step for
man, one giant leap for mankind.”
- NEIL ARMSTRONG