We define Force as:

1) Force is a push or pull.

2) Force is the capacity to do work or cause physical change.

3) Force= Mass times acceleration (F = ma)

4) A force is that which changes or tends to change the state of rest or

motion of a body.

motion of a body.

**Let’s See Some Examples here**

For simplicity sake, all forces (interactions) between objects can be

placed into two broad categories: contact forces, and forces resulting from

action-at-a-distance.

placed into two broad categories: contact forces, and forces resulting from

action-at-a-distance.

also,

Contact Forces include frictional forces, buoyant forces, normal forces,

and air resistance forces….

and air resistance forces….

while,

Action-at-a-distance forces include gravitation, electrostatic and magnetic

forces.

forces.

**Measurement of Force**

Force is measured using either the English System of Measurements or the

International System of Units (SI).

International System of Units (SI).

the most Common Units of Force are as following;

—>>SI: Newton (N) 1 N = 0.225 lb;

One Newton (N) of force is

defined as the amount of force needed to accede of mass at a rate of 1 meter per second squared (m/s^2).

defined as the amount of force needed to accede of mass at a rate of 1 meter per second squared (m/s^2).

1 Newton = 1 kg m/sec2 (A kilogram is the amount of weight at which 1 N of

force will accelerate at a rate of 1 m/s^2.)

force will accelerate at a rate of 1 m/s^2.)

—>>English System: Pound (LB) 1 LB = 4.448 N

In English system of measurements, a slug is the amount of mass that 1

pound of force will accelerate at 1 ft/s^2, and a pound mass is the amount of

mass that 1 LB of force will accelerate at 32 feet/s^2.

pound of force will accelerate at 1 ft/s^2, and a pound mass is the amount of

mass that 1 LB of force will accelerate at 32 feet/s^2.

**Description of a Force**

A force is a vector quantity. A vector quantity is a quantity which has

both magnitude and direction. To fully describe the force acting upon an

object, you must describe both its magnitude and direction.

both magnitude and direction. To fully describe the force acting upon an

object, you must describe both its magnitude and direction.

Thus we see, 10 Newtons of force is not a complete description of the force

acting on an object. 10 Newtons, downwards is a complete description of the

force acting upon an object.

acting on an object. 10 Newtons, downwards is a complete description of the

force acting upon an object.

**Now we must learn What the**

difference between vector and scalar quantities is?

difference between vector and scalar quantities is?

A vector has both strength and

direction, a scalar quantity can be described using only 1 quantity, magnitude.

direction, a scalar quantity can be described using only 1 quantity, magnitude.

Example of vector quantities are

velocity, acceleration etc.

velocity, acceleration etc.

Examples of scalar quantities are

time, energy and volume since they only represent magnitude and no direction.

time, energy and volume since they only represent magnitude and no direction.

**What is the Difference between**

Mass and Weight?

Mass and Weight?

Shown below are two types of

scales commonly used in the classroom –a spring scale (left) and a simple

balance beam scale on the right.

scales commonly used in the classroom –a spring scale (left) and a simple

balance beam scale on the right.

On earth the spring scale reads

100g with an unknown mass attached at the bottom. To balance the scale on the

right a 100g mass was also needed.

100g with an unknown mass attached at the bottom. To balance the scale on the

right a 100g mass was also needed.

If we were to take both scales to the moon,

what would the the spring scale read? How much mass would be needed to balance

the 100g mass on the balance beam?

what would the the spring scale read? How much mass would be needed to balance

the 100g mass on the balance beam?

**What does applying a Force do?**

Force causes acceleration

Newton’s Second Law states that:

the acceleration (a) of an object is directly proportional to the force (F)

applied, and inversely proportional the object’s mass (m).

the acceleration (a) of an object is directly proportional to the force (F)

applied, and inversely proportional the object’s mass (m).

That means that the more force

you apply to an object, the greater the acceleration. And, the more mass the

object has, the lower the acceleration.

you apply to an object, the greater the acceleration. And, the more mass the

object has, the lower the acceleration.

**Newton’s Second Law can be**

written in equation form:

written in equation form:

F = ma.

For falling objects we can write

F=mg where g is the acceleration due to gravity. The force of gravity is what

causes free falling objects to accelerate. These objects all accelerate at the

same rate of 9.8 meters/sec^2.

F=mg where g is the acceleration due to gravity. The force of gravity is what

causes free falling objects to accelerate. These objects all accelerate at the

same rate of 9.8 meters/sec^2.

**What is Friction?**

Friction is the force that

opposes the relative motion or tendency to such motion of two bodies in

contact. If we try to push a block of wood across a table, there are two

opposing forces that act: the force associated with the push, and a force that

is associated with the friction which acts in the opposite direction. As

frictional forces are decreased (for example, by placing oil on the table) the

object moves further and further before stopping. This demonstrates Galileo’s

law of inertia too.

opposes the relative motion or tendency to such motion of two bodies in

contact. If we try to push a block of wood across a table, there are two

opposing forces that act: the force associated with the push, and a force that

is associated with the friction which acts in the opposite direction. As

frictional forces are decreased (for example, by placing oil on the table) the

object moves further and further before stopping. This demonstrates Galileo’s

law of inertia too.

@arushi mam??

Yes

Gud morning mam….happy shivratri..F5

Thank u Ayushi mam for this valuable post …__/__

Yeah..its really awsm

GA Sam. Thank You and same to u 🙂

gm sam

शिव की शक्ति, शिव की भक्ति, ख़ुशी की बहार मिले,

शिवरात्रि के पावन अवसर पर आपको ज़िन्दगी की एक नई अच्छी शुरुवात मिले!

शिवरात्रि की हार्दिक शुभकामनायें!

Gm shadow….how r u??

fine and u

Thanq mam…nd welcm

Me as usual fyn…

Hey,dear thanq nd wish u d same

ok,,

cgl 2015 ki preparation kaise chal rhi hai

Yar,, I was focusing on bank po ,,bt ayushi mam k post se aisa feel ho raha hai kk from nw onwards I must prepare for cgl 2015 as well

have u given po interview?

Dear I dint qualify…..bt did tym I will…

gud luck dear….

U too shadow…may dis year v both will get job….

@arushi mam?

Yes Shadow?

Good Morning mam…

happy shivratri…..

Thank You and same to you! 🙂

mam pls provide ECONOMY notes in pdf based on NCERT book

Ayushi mam..plz fci ka syllabus nd previous year cut off jaroor post kriyega…it will help to achieve desired results to all of us

@@shadow

We will try and post it Sam!

Olryt mam…

Shadow we post questions related to economics.

As far as notes are concerned, we will try and make a post for it too!

thanks a lot mam __/__

yes

Year meko ye btao k fci me generalist or depot k liye sirf 1 paper h na…120 questns nd 90 mints

Sir/madam,

What is approximate date of cgl 2014 tier 2?

It was scheduled to be held in January. Since it is postponed, official date is yet to be announced..

generalist or general

Arey baba its understood na…olryt general..ab btao

yes paper 1 he hai

Ok….nd graduation % ka koe issue to ne hai..means 69% must or smthing

sorry i have not read whole notification, can not say about %

Thankyou mam/sir :))Data Interpretation Quiz

http://www.sscadda.com/2015/02/data-interpretation-quiz.html

ssc adda also should be in hindi language

_/_