Newtons laws in practical life..& its explanation...

2. WeAre… GroupNo: 12
SERIAL
NO.
Name Id no.
01 RASHEL AHMED 21-034
02 RUMANA BARKAT RUMU 21-191
03 MAIMUNAAKTER 21-121
04 Md. MAHABUB ALAM 21-260
05 PRANAB CHANDRA GHOSH 21-265

3. Our respected course teachers are:
Course Name: General Science & Environment(F-110)
Dept. of Finance , University of Dhaka
Dr. Md. Zahangir Alam
Professor(Dept. of Applied Chemistry & Chemical
Engineering, DU)
Dr. Ratan Chandra Gosh
Associate Professor (Dept. of Physics, DU)

4. We are Assigned…
Applications of Newton’s Laws in Real Life

5. Now You are with…
RASHEL AHMED
Id No: 21-034

7. Newton’s law of Motion
Sir Isaac Newton discovered the 3 laws of motion.
1st law(Inertia)
2nd law
3rd law

8. Newton’s Laws of Motion
Newton’s First Law:
Objects in motion tend to stay in motion and objects at rest
tend to stay at rest unless acted upon by an unbalanced
force.
Newton’s Second Law:
Force equals mass times acceleration (F = ma).
Newton’s Third Law:
For every action there is an equal and opposite reaction.

9. Now You are with…
MAIMUNA AKTER
ID No: 21-121

10. An object at rest tends to stay at rest and an
object in motion tends to stay in motion
unless acted upon by an unbalanced force.
Newton’s First Law
Newton’s First Law of Motion

11. Newton’s 1st law
Newton’s First Law of Motion

12. What does this mean?
 Basically, an object will “keep doing what it was
doing” unless acted on by an unbalanced force.
 If the object was sitting still, it will remain
stationary. If it was moving at a constant velocity, it
will keep moving.
 It takes force to change the motion of an object.

13. Law of Inertia
Newton’s first law is also called law of inertia.
Inertia: It is the inability of the body to change the
state of motion and its state of rest by itself.
Which is directly related to the first law of Motion.

14. Newton’s First Law

15. Real life examples of Newton's first law
1.When a bus suddenly starts, the passengers sitting
or standing in the bus tend to fall backward. This is
due to inertia of rest and can be explained as
follows: when the bus suddenly starts, the lower
part of the body of the passenger which is in contact
with the bus moves along with the bus while the
upper part of the body tends to retain its state of rest
due to inertia. As a result, the passenger falls
backward.

16. Real life examples of Newton's first law

17. Real life examples of Newton's first law
2. When a branch of a tree is vigorously shaken
the fruits and seeds in It fall down to inertia of
rest.

18. Real life examples of Newton's first law
3. A rider on a running horse is thrown forward
when the horse stops suddenly due to inertia of
motion.

19. Now You are with…
Md. MAHABUB ALAM
Id No: 21-260

20. Force equals mass times acceleration.
F = ma
Newton’s Second Law
Acceleration: a measurement of how quickly an object is
changing speed.
Newton’s Second Law

21. Newton’s Second Law
Force is directly proportional to mass and
acceleration. Which is F=ma.
* Imagine a ball of a certain mass moving at a certain
acceleration. This ball has a certain force.
* Now imagine we make the ball twice as big (double
the mass) but keep the acceleration constant. F = ma
says that this new ball has twice the force of the old
ball.

22. Newton’s Second Law
* Now imagine the original ball moving at twice the
original acceleration. F = ma says that the ball will
again have twice the force of the ball at the original
acceleration.

23. What does F = ma say?
 F = ma basically means that the force of an object
comes from its mass and its acceleration.
 If you double the mass, you double the force. If you
double the acceleration, you double the force.
 Doubling the mass and the acceleration quadruples
the force.
(2m)(2a) = 4F
So . . . what if you decrease the mass by half? How
much force would the object have now?

24. Real life examples of Newton's 2nd law
THIS LAW STATES…
Newton's second law states that the speed of
acceleration of a moving object depends on the
object's mass and the force being exerted on it.

25. Real life examples of Newton's 2nd law
1. One instance of this is the understanding that it
requires much more force to push a vehicle than to
kick a soccer ball.

26. Real life examples of Newton's 2nd law
2. Simply, Newton's second law represents the fact that
the greater the mass of an object, the more force
there is needed in order to move it. This explains
why, for example, it requires one person to easily lift
a box weighing five pounds but multiple people
exerting more force collectively to lift a box
weighing 100 pounds.

27. Real life examples of Newton's 2nd law

28. Now You are with…
RUMANA BARKAT RUMU
ID NO:21-191

29. Newton’s Third Law of Motion
For every action there is an equal and opposite
reaction.

30. “In every action, there is always an equal and
opposite reaction”

31. Newton’s Laws of Motion
 3rd Law States – When one object exerts a
force on another object, the 2nd object exerts an
equal and opposite force back on the 1st object.

32.  While firing a bullet , the gun must be held tight
to the shoulder.
 When a man jumps from a boat to the shore, the
boat slightly moves away from the shore.
 When a bullet is fired from a gun, the gun
recalls or gives a kick in backward direction.
 Rocket works on the principle of conservation
of momentum.
 If some one left on a frictionless floor desire to
get out of it, he can do so by blowing air out of
his mouth.

33. Newton’s 3rd Law in Nature
 Consider the propulsion of a
fish through the water. A
fish uses its fins to push
water backwards. In turn,
the water reacts by pushing
the fish forwards, propelling
the fish through the water.
 The size of the force on the
water equals the size of the
force on the fish; the
direction of the force on the
water (backwards) is
opposite the direction of the
force on the fish (forwards).

34. Newton’s 3rd Law in Nature
Flying gracefully
through the air, birds
depend on Newton’s
third law of motion. As
the birds push down on
the air with their wings,
the air pushes their
wings up and gives
them lift.

35. Other examples of Newton’s
Third Law
 The baseball forces
the bat to the left (an
action); the bat forces
the ball to the right
(the reaction).

36. Application of Newton’s 3rd Law

37. Application of Newton’s 3rd Law
The reaction of a rocket is
an application of the third
law of motion. Various
fuels are burned in the
engine, producing hot
gases.
The hot gases push against
the inside tube of the rocket
and escape out the bottom
of the tube. As the gases
move downward, the rocket
moves in the opposite
direction.

38. Now You are with…
PRANAB CHANDRA GHOSH
ID No: 21-265

39. Newton’s Laws(Cont’d)

40.  The idea of gravity was Introduced by Sir Isaac
Newton in the late 1600’s
 He was a scientist who combine ideas
to explain how the universe operates

41. All Matter Is Affected by Gravity
 Because of gravity you are being pulled toward your
book, your pencil, and every other object around you.
 You exert an attractive force on everything around you
and everything is exerting an attractive force on you.
 This attractive force is called gravity.
 All objects experience an attraction toward all other
objects in this universe.

42. Newton’s Universal Law of Gravitation(Cont’d)
This Law States…..
Every particle of matter in the universe attracts every
other particle with a force that is directly proportional
to the product of the masses of the particles and
inversely proportional to the square of the distance
between them.

43. Gravitational Force
Gravitation force depends on two things:
• The mass of the two objects
• The distance between the two objects
G  The Universal Gravitational Constant
› It is the same everywhere in the Universe
G = 6.673  10-11 N∙m2/kg2
Always same on every location

44.  Gravitational force is directly proportional to the
product of masses.
Newton’s Universal Law of Gravitation(Cont’d)

45. Gravitational Force and Distance
 Gravity between any person and the earth is greater
than the gravity between the person and the sun.
Gravitational force decreases as distance increases.
Newton’s Universal Law of Gravitation(Cont’d)

46.  Gravitational force is inversely proportional to
the square of distance between the masses

47. Gravitational Force and Mass
 Earth attracts an elephant more than
a cat.
 Earth attracts coconut more than an apple.
 Earth’s gravitational force is greater than that of
moon.
Gravitational force increases as mass increases.

48. Mass, Distance AND Gravitational Force

49. Examples of Gravitation......
Some examples are—

50. Examples of Gravitation......
Brick’s recurring pushing on
ground

51. Any Query?