Force and Pressure | Full Chapter Revision under 30 mins | Class 8 Science

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[KunalSharma-hcpx]

Ans is Camels can walk easily in the desert because of their wide feet. Their wide feet allow the weight of their body to act on a larger surface of land reducing the pressure exerted on the land by the camel. As we know, pressure exerted and area are inversely proportional.

[aryamankaushik]

in the first question:
It is more difficult for the horse to walk in the sand because its feet are not broad as that of a camel. Which means less surface area, and pressure exerted on the sand is more hence the feet of the horse going inside the sand.
Q-2) B 12.5:1
Hint to those who are solving: An elephant has 4 feet not 1.

[Artsmosphere]

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[poshali]

THANKYOU SIR FOR BRINGING THIS SESSION FOR US!..
THIS CHAPTER IS COMING IN MY ANNUAL EXAMINATION ALSO!.... 😊😊

[RouhanKhan-rfcp]

Q1( b) 12.5 : 1, Q2/ Ans The horse is unable to walk on the desert because it's feets have small area that exerts more pressure, but a camel walks easily on desert because it's feets are
broad that increases area because of this pressure is low that is why camel walks easily in desert and not gets inside the sand .

[YashikaSolanki-nmcc]

VERY NICE SESSION I LIKE THESE TYPE OF SESSIONS MY EXAMS R FROM 28 FEB TO 11 MAR I ALSO WANT EXEMPLER QUESTION SIR THANK U SOOOO

[Priya_sharma]

Hello sir thank you for this chapter and homework answer is :-
1. camels have broad feet than horse though which they can run easily while horses have solid feet so they sink easily in desert.
2. The ratio is 12.5 : 1
If there is any mistake please tell me sir 😅

[randomguy-nxrx]

12:39 homework question answer (a) since the formula of pressure is f/a
then the pressure exerted by the girl = 50/1 (applied force of 50 and area of 1) which is 50 pascals
then pressure exerted by elephant = 2000/250 which is 200/25 which is 8 pascals
ratio = 50:8 which can be represented as 50/8 which is 25/4 which can be written as 6.25:1

[YashikaSolanki-nmcc]

IT IS EASIER FOR A CAMEL TO MOVE ON SAND THAN HORSE BECAUSE CAMEL HAS BROAD FEET HENCE LARGE AREA SO PRESSURE EXERTED WILL BE LESS

[KunalSharma-hcpx]

What you're solving for The ratio of pressure exerted by the girl to that by the elephant.
What's given in the problem
The girl weighs 50 N
The girl wears pencil heels sandals each of area 1cm square
The elephant weighs 2000N
The elephant stands on foot each of area 250cm square
How to solve
Calculate the pressure exerted by the girl and the elephant, then divide the pressure exerted by the girl by the pressure exerted by the elephant.
Step 1
Calculate the pressure exerted by the girl.
Pressure =force upon area
Pressure = 50 N upon 1cm square
Pressure = 50N/cm square
Step 2
Calculate the pressure exerted by the elephant.
Pressure = Force upon Area
Pressure = 2000N upon 250cm square
Pressure = 8N/cm square
Step 3
Divide the pressure exerted by the girl by the pressure exerted by the elephant.
50N/cm square upon 8N/cm square = 6.25
Solution The ratio of pressure exerted by the girl to that by the elephant is 6.25.

[shauryadhanekar]

11:24
Answer: the camels 🐫has large foot then horse 🐎 so they can walk on sand because the ptessure will be distributed on the sand but in the case of horse they have shor foot so they can stuck in the sand

[ahmedpasha]

Hi 2nd comment
Byjus you are just wonderful you help a lot of young learners on this platform 🤠 hats of to you ❤🔥🔥

[sonujaiman]

28 March se kis kis ke tension start ho Rahi h RBSC Wale best of luck

[swapnaputtapalli]

The correct answer of second question is 25 is to 1 because

The elephant has four foots each is 250cmsquare for 4 ft it is 1000 CM
Show the pressure of elephant is 2000 by 1000 which the pressure is 2.

The girls pressure is 50 / 1 which is equals to 50

50 /2 which is equals to 25 is to 1

[Kingeadly]

11:20 Because the camel has broader feet than of horse which increases area on sand due to which the preasure is decreased and it doesn't sink in it.
Am I right?

[atainakhan]

Force and Pressure
❖ The force that acts on a surface in a direction perpendicular to it, is known as thrust.
Pressure
❖ Thrust per unit area is called pressure. So, pressure = force/area on which it acts.
❖ Liquids exert pressure on the walls of the container in which they are kept.
❖ Gases exert pressure in all directions.
Electrostatic Force
❖ A force exerted by a charged body on another charged or uncharged body is known as electrostatic force.
❖ Atmospheric pressure is defined as the pressure exerted on a surface by the weight of air above that surface.
Atmospheric Pressure
❖ The pressure exerted by atmospheric air around us is known as atmospheric pressure.
Contact Force
❖ A force that can be applied only when it is in contact with an object is called a contact force. For example,
hammering a nail.
Electrostatic Force
❖ When a charged body, either having a (+) or (–) charge, exerts force on another charged or uncharged body, that
force is known as electrostatic force.
Force
❖ Simply a push or pull exerted by an object on another is a force.
Friction
❖ The force of friction always acts on all the moving objects and its direction is always opposite to the direction of
motion.
Gravitational Force
❖ The force exerted by the earth to pull the objects towards itself is called the force of gravity.
Gravity
❖ Every object in the universe, whether small or large, exerts a force on every other object. This force is called the
force of gravity or just gravity.
Magnetic Force
❖ The force exerted by a magnet to pull/push a metallic object is called magnetic force.
Muscular Force
❖ The force resulting due to the action of muscles is known as muscular force. For example, writing, cutting
vegetables.
Non-Contact Forces
❖ A force that can be applied without any contact between two objects is called non-contact force. For example,
the magnet pulls the iron-pieces.
Pressure
❖ The force acting on per unit area, applied to an object in the direction perpendicular to the surface is called
pressure.

[sanskritigupta]

Homework question answer

Option a 6.25:1

Solution -
Pressure = trust

Area
Case 1
Girl- trust = 50N
Area = 1cm2
Case - 2
Elephant - trust 2000N
Area - 250cm2
= 8
.
. . 50

8
= 6.25:1 ans

[brajesh]

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[sangitasharma]

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[sahib]

We use camels rather than horses as horse have small feet and exert more Pressure on sand hence they can't be used in deserts as they can't move while horses have padded feet which allow them to exert less pressure on sand