Ask questions which are clear, concise and easy to understand.
Ask QuestionPosted by Vivek Kumar 3 years, 11 months ago
- 1 answers
Posted by Banarasiya Don???? 3 years, 11 months ago
- 4 answers
Posted by Nikhil Kumar 3 years, 11 months ago
- 5 answers
Bani Singh Bani Singh 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
Non-contact Forces : The force experienced by the bodies even without being physically touched, are called non-contact forces. e.g. Gravitational force, Magnetic force.
Posted by Nikhil Kumar 3 years, 11 months ago
- 4 answers
Shreya Jha 3 years, 10 months ago
Bani Singh Bani Singh 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
Contact Forces : The forces which are applied on bodies by making a physical contact with them, are called contact forces. e.g. the force of friction (frictional force), normal reqction force
Posted by Bhumika Choudhary 3 years, 11 months ago
- 2 answers
Gaurav Seth 3 years, 11 months ago
(a) Saloni should add some water in the test tube in which gas was collected. Shake the test tube and then bring a litmus paper near the test tube.The solution will turn litmus paper red. This shows that the gas is acidic.
(b)Charcoal contains carbon which on burning forms carbon dioxide gas.
C+O_2→CO_2C+O2→CO2
The gas evolved is collected in a test tube and water is added to it.
CO_2+H_2O→H_2CO_3CO2+H2O→H2CO3
Posted by Vipul Atri 3 years, 11 months ago
- 4 answers
Shreya Jha 3 years, 10 months ago
Shreya Jha 3 years, 10 months ago
Banarasiya Don???? 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
In order to provide food for a large population – regular production, proper management and distribution of food is necessary.
Crop: When plants of the same kind are grown and cultivated at one place on a large scale, it is called a crop.
- In India, crops can be broadly categorised into two types based on seasons – Rabi and Kharif crops.
- Sowing of seeds at appropriate depths and distances gives good yield. Good variety of seeds are sown after selection of healthy seeds. Sowing is done by seed drills.
- Soil needs replenishment and enrichment through the use of organic manure and fertilisers. Use of chemical fertilisers has increased tremendously with the introduction of new crop varieties.
For more click on the given link:
<a data-ved="2ahUKEwjp8o747-rtAhXWTX0KHZmVBUYQFjAAegQIBRAC" href="https://mycbseguide.com/blog/cbse-class-8-science-revision-notes/" ping="/url?sa=t&source=web&rct=j&url=https://mycbseguide.com/blog/cbse-class-8-science-revision-notes/&ved=2ahUKEwjp8o747-rtAhXWTX0KHZmVBUYQFjAAegQIBRAC" rel="noopener" target="_blank">CBSE Class 8 Science Revision Notes | myCBSEguide ...</a>
Posted by Banarasiya Don???? 1 year, 8 months ago
- 2 answers
Gargi Bhiwapurkar 1 year, 8 months ago
Posted by Banarasiya Don???? 3 years, 11 months ago
- 1 answers
Gaurav Seth 3 years, 11 months ago
Incident ray : Incident ray is define as that ray of light which falls on the mirror surface. Here AO is the incident ray.
⇒Reflected ray : The ray of light which is sent back by the mirror is known as reflected ray. Here OB is the reflected ray.
⇒Point of incidence : The point at which incident ray falls on the mirror is called point of incident . Here o is the point of incidence.
⇒Normal : The normal is the line at right angle to the mirror surface at the point of incidence.
⇒Angle of incidence : This is the angle made by the incident ray with the normal at the point of incidence.
⇒Angle of reflection : This is the angle made by the reflected ray with the normal at the point of incident.
<button role="button" title="enlarge image"></button>
<button role="button" title="rotate image"></button>
Posted by Ashwin Jadhav 3 years, 11 months ago
- 0 answers
Posted by Ashwin Jadhav 3 years, 11 months ago
- 1 answers
Posted by Ayush Pawar 3 years, 11 months ago
- 1 answers
Yogita Ingle 3 years, 11 months ago
The endocrine glands release hormones into bloodstream to reach a particular body part called target site. The target site responds to the hormone. the particular site where the hormones reach through the bloodstream is called the target site.
Posted by Ayush Pawar 3 years, 11 months ago
- 1 answers
Shruti ? 3 years, 11 months ago
Posted by Bani Singh Bani Singh 3 years, 11 months ago
- 1 answers
Shruti ? 3 years, 11 months ago
Posted by Ramanpreet Kaur 3 years, 11 months ago
- 1 answers
Gaurav Seth 3 years, 11 months ago
i-low, ii-spontaneous, iii-Kerosene
The minimum temperature at which a substance catches fire is called ignition temperature. The ignition temperature of sodium is very low. Hence, it catches fire easily at room temperature. It reacts vigorously with oxygen at room temperature. To prevent its spontaneous combustion, it is stored under kerosene.
Posted by Bani Singh Bani Singh 3 years, 11 months ago
- 2 answers
Gaurav Seth 3 years, 11 months ago
The SI unit of pressure is Pascal (represented as Pa) which is equal to one newton per square metre (N/m-2 or kg m-1s-2). Interestingly, this name was given in 1971. Before that pressure in SI was measured in newtons per square metre.
Pascal Formula:
Posted by Sai Varsha 3 years, 11 months ago
- 3 answers
Ashutosh Shukla 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
The Acts of Union, passed by the English and Scottish Parliaments in 1707, led to the creation of the United Kingdom of Great Britain on 1 May of that year. ... The idea of a union between England and Scotland was aired in February and March 1689 during the deliberations of the Convention Parliament in Edinburgh.
Yogita Ingle 3 years, 11 months ago
Synthetic fibres are man-made fibres, most of them are prepared from raw material petroleum called petrochemicals. All fabrics are obtained from fibres, while fibres are obtained from artificial or man-made sources. They consist of a small unit or a polymer which is made from many repeating units known as monomers. They include nylon, acrylics, polyurethane, and polypropylene. Millions of tons of these fibres are produced all over the world each year.
Posted by Mahesh Yadav Kotla 3 years, 11 months ago
- 1 answers
Gaurav Seth 3 years, 11 months ago
Some fibres are called synthetic because they are not made from natural fibres. Instead, they are made by chemical processing of petrochemicals. The synthetic fibres are made up of very large units called polymers. Some of the synthetic fibres are - nylon, rayon, acrylon.
Posted by Simran Singh 3 years, 11 months ago
- 2 answers
Niraj Chaudhary 3 years, 11 months ago
Yogita Ingle 3 years, 11 months ago
at the time of puberty, and usually is around two years earlier in females than man.
The secondary sexual characteristics in males are :
Hair growth on the face in the form of beard and moustache
The growth of his testicles
Heavier musculature
Adam's apple development
Larynx becomes larger results in a deeper voice
Some of the changes appear in females are:
Development of breast
Lighter musculature
Shrill and a higher pitch voice
Broadening of hips due to fat deposition
Posted by Ankit Chhawadi Rashmi Chhawdi 3 years, 11 months ago
- 1 answers
Yogita Ingle 3 years, 11 months ago
Two examples of push force are as follows:
- A heavy box at rest is pushed to move it from one room to another. This changes the state of motion of the box.
- A player pushes a football using his foot. This changes the state of motion of the ball.
Two examples of pull force are as follows:
- Rope is pulled to draw water from a well. This changes the state of motion of the water bucket.
- A drawer is pulled to open it. This changes the state of motion of the drawer.
Posted by Kishore K.V 3 years, 11 months ago
- 4 answers
Gaurav Seth 3 years, 11 months ago
The moon never actually falls on the surface of the earth.
Now, to understand this, we first need to understand the nature of the force between the moon and earth and also the movement of the moon under this force.
So, the gravitational force is the force that acts between the earth and the moon, and the moon moves in the circular orbital due to the centripetal force generated by the gravitational force.
Similarly, earth and sun also experience this gravitational force between themselves.
So, yes the moon does fall towards the earth, but the earth also moves in its orbit and covers more distance away from the moon relative to the distance covered by the moon.
Hence, the moon never falls on the surface of the earth
Posted by Tania Sharma 3 years, 11 months ago
- 3 answers
Gaurav Seth 3 years, 11 months ago
A n s w e r:
A rough surface causes more friction because the irregularities on the rough surface are more when compared to the smooth surface. These irregularities helps in increasing the friction.
Hardik Garg 3 years, 11 months ago
Posted by Khushi Goyal 3 years, 11 months ago
- 1 answers
Gaurav Seth 3 years, 11 months ago
Ans:
static, sliding, rolling
Friction comes into play when irregularities present in the surfaces of two objects in contact get interlocked with each other. Static friction comes into play when we try to move an object which is at rest. Sliding friction comes into play when an object slides over the surface of another object. In sliding friction, the time given for interlocking is very small. Hence, interlocking is not strong. Therefore, less force is required to overcome this interlocking. Because of this reason, sliding friction is less than static friction. Similarly, the area of contact in case of rolling friction is smallest as compared to static or sliding friction. This area of contact changes gradually because of rolling. Hence, rolling friction is lesser than both static and sliding friction. Thus, the correct sequence is—static, sliding, rolling
Posted by Khushi Goyal 3 years, 11 months ago
- 1 answers
Gaurav Seth 3 years, 11 months ago
static, sliding, rolling
Friction comes into play when irregularities present in the surfaces of two objects in contact get interlocked with each other. Static friction comes into play when we try to move an object which is at rest. Sliding friction comes into play when an object slides over the surface of another object. In sliding friction, the time given for interlocking is very small. Hence, interlocking is not strong. Therefore, less force is required to overcome this interlocking. Because of this reason, sliding friction is less than static friction. Similarly, the area of contact in case of rolling friction is smallest as compared to static or sliding friction. This area of contact changes gradually because of rolling. Hence, rolling friction is lesser than both static and sliding friction. Thus, the correct sequence is—static, sliding, rolling
Posted by Gobinda Chandra Hembram 3 years, 11 months ago
- 5 answers
Yogita Ingle 3 years, 11 months ago
Cells are the fundamental structural units of living organisms and the basic units of life.
Neha Sanotra 3 years, 11 months ago
Posted by Vaishnavi Ghag 3 years, 11 months ago
- 2 answers
Gaurav Seth 3 years, 11 months ago
Solution :-
- 1 m² = 10000cm²
- Area = 0.1 m²
As we know that
→ Pressure = Force/Area
→ Pressure = 20,000/0.1
→ Pressure = 200000 N/m²
Hence,
- Pressure would it exert on the ground is 200000 N/m²
Extra Information :-
- S.I unit of Pressure is N/m²(Pascal)
- 1000m = 1km
- 1m = 100cm
- S.I unit of Force is Newton (N)
- S.I unit of Area is m²
Yogita Ingle 3 years, 11 months ago
- 1 m² = 10000cm²
- Area = 0.1 m²
As we know that
→ Pressure = Force/Area
→ Pressure = 20,000/0.1
→ Pressure = 200000 N/m²
Hence,
- Pressure would it exert on the ground is 200000 N/m²
Posted by Revanth Reddy 3 years, 11 months ago
- 3 answers
Gaurav Seth 3 years, 11 months ago
Generally, water is used to control fire. Water brings down the temperature of the combustible substance below its ignition temperature. The water vapour surrounds the combustible material, thus helping in cutting off the supply of air. So, that the fire is extinguished.
Posted by Unnati Bariya 3 years, 11 months ago
- 5 answers
Ganesa Mani S 3 years, 11 months ago
Unnati Bariya 3 years, 11 months ago
Rohit Panghal 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
C o n t a c t f o r c e s : Force that arises with the contact of 2 or more objects involved. Examples : Muscular force and Frictional Force
Revanth Reddy 3 years, 11 months ago
Posted by Princejeet Kaur 3 years, 11 months ago
- 2 answers
Akshita Rana 3 years, 11 months ago
Yogita Ingle 3 years, 11 months ago
Calorific value is the amount of heat energy present in food or fuel and which is determined by the complete combustion of specified quantity at constant pressure and in normal conditions. It is also called calorific power. The unit of calorific value is kilojoule per kilogram i.e. KJ/Kg.
Posted by Shridhar Vyas 3 years, 11 months ago
- 5 answers
Gaurav Seth 3 years, 11 months ago
Cellulose
Cellulose is a long chain of linked sugar molecules that gives wood its remarkable strength. It is the main component of plant cell walls, and the basic building block for many textiles and for paper. Cotton is the purest natural form of cellulose. Plant cell wall is not made of glucose, fructose or starch.
Posted by Sachin Kumar 3 years, 11 months ago
- 5 answers
Yatan Batth 3 years, 11 months ago
Vijaya Laxmi 3 years, 11 months ago
Hardik Garg 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
Microbes are also used to prepare antibiotics, which are used to treat several bacterial infections. Antibiotics are chemical substances that kill disease-causing microbes. It is quite interesting to find that there are some microbes which cause diseases; on the other hand, some other microbes help in preparation of antibiotics, and thus, cure diseases.
Yogita Ingle 3 years, 11 months ago
Microbes are also used to prepare antibiotics, which are used to treat several bacterial infections. Antibiotics are chemical substances that kill disease-causing microbes. It is quite interesting to find that there are some microbes which cause diseases; on the other hand, some other microbes help in preparation of antibiotics, and thus, cure diseases.
myCBSEguide
Trusted by 1 Crore+ Students
Test Generator
Create papers online. It's FREE.
CUET Mock Tests
75,000+ questions to practice only on myCBSEguide app
Ayush Sharma 3 years, 11 months ago
3Thank You