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Ask QuestionPosted by Pratibha Kushwah 4 years, 11 months ago
- 1 answers
Yogita Ingle 4 years, 11 months ago
The example of diffusion of gases in liquids is: Oxygen (gas) gets dissolved in blood (liquid) during the process of respiration.
Posted by Pratibha Kushwah 4 years, 11 months ago
- 1 answers
Yogita Ingle 4 years, 11 months ago
Water at room temperature does not have a fixed shape but flows to take the shape of the container. Hence, water at room temperature is a liquid.
An iron almirah is a solid at room temperature because its melting point as well as boiling point is above room temperature.
Posted by Pratibha Kushwah 4 years, 11 months ago
- 5 answers
Yogita Ingle 4 years, 11 months ago
Gases have neither fixed shape nor fixed volume. This is because of the weak intermolecular foces of attraction in the gases. They take the shape and volume of the container in which they are placed.
Abhishek Kumar 4 years, 11 months ago
Posted by Punit Kadyan 4 years, 11 months ago
- 1 answers
Posted by Srushti Khadtare 4 years, 11 months ago
- 1 answers
Yogita Ingle 4 years, 11 months ago
If α-particle scattering experiment is carried out using a foil of any metal as thin as gold foil used by Rutherford, there would be no change in observations if heavy metal like gold use for example Platinium, sliver. but if it would be taken by light metal like lithium than the massive alpha particles will push the nucleus and may not be deflected back.
Posted by Mishika Pandey 4 years, 11 months ago
- 3 answers
Neelesh Verma 4 years, 11 months ago
Taniya Chauhan 4 years, 11 months ago
Posted by Kavita Mani Tripathi 4 years, 11 months ago
- 3 answers
Neelesh Verma 4 years, 11 months ago
Ananya K 4 years, 11 months ago
Gaurav Seth 4 years, 11 months ago
Derivation of Newton’s third law of motion from Newton’s second law of motion
Consider an isolated system of two bodies A & B mutually interacting with each other, provided there is no external force acting on the system.
Let FAB, be the force exerted on body B by body A and FBA be the force exerted by body B on A.
Suppose that due to these forces FAB and FBA, dp1/dt and dp2/dt be the rate of the change of momentum of these bodies respectively.
Then, FBA = dp1/dt ---------- (i)
=> FAB = dp2/dt---------- (ii)
Adding equations (i) and (ii), we get,
FBA + FAB = dp1/dt + dp2/dt
⇒ FBA + FAB = d(p1 + p2)/dt
If no external force acts on the system, then
d(p1 + p2)/dt = 0
⇒ FBA + FAB = 0
⇒ FBA = - FAB---------- (iii)
the above equation (iii) represents the Newton's third law of motion (i.e., for every action there is equal and opposite reaction).
Posted by Sakshi Kamble 4 years, 11 months ago
- 1 answers
Ananya K 4 years, 11 months ago
Posted by Muskan Student 4 years, 11 months ago
- 3 answers
Gaurav Seth 4 years, 11 months ago
Answer:
Helium has two electrons in its energy shell, while argon and neon have 8 electrons in their valence shells. As these have maximum number of electrons in their valence shells, they do not have any tendency to combine with other elements. Hence, they have a valency equal to zero.
Meghna Thapar 4 years, 11 months ago
Valency is defined as the measure of the combining power with other atoms when it forms a molecule of compound. ... Noble gases have valency 0 because these elements cannot loose or gain electrons. The electrons are fully filled in the sub-shells of these elements. hence, the valency of these elements is 0. Helium has two electrons in its only energy shell. ... As the elements have the maximum number of electrons in their valence shells (thereby achieving stable duplet and octet configurations), they do not have any tendency to combine with other elements. Hence, Helium, Neon, and Argon have zero valency.
Posted by Gulshan Kumar 4 years, 11 months ago
- 1 answers
Yogita Ingle 4 years, 11 months ago
- A coil with many circular close turns of insulated copper wire (like a cylinder as shown above) is a solenoid.
- One end of such a solenoid behaves like the north pole and the other as a south pole.
Posted by Akshita ???? 4 years, 11 months ago
- 2 answers
Taniya Chauhan 4 years, 11 months ago
Yogita Ingle 4 years, 11 months ago
Consider a body having large mass and large weight. Example of this situation is a large object which is hard to throw because the weight of this object is large.
Therefore, the relation between weight and mass can be derived with the help of Newton’s second law which explains that the free falling object has an acceleration “g” as the magnitude.
If an object with a mass of 1kg falls with an acceleration of 9.8 m.s-2, then the magnitude of the force is given as :
F = ma
= (1kg)(9.8m.s-2)
= (9.8 kg.m.s-2)
= 9.8N
Therefore, it can be concluded that the relation between weight and mass of an object with 1kg mass will have a weight of 9.8N.
Posted by Om Chavhan 4 years, 11 months ago
- 2 answers
Aarushi Erande 4 years, 11 months ago
Pratibha Kushwah 4 years, 11 months ago
Posted by Swayam Deep 4 years, 11 months ago
- 2 answers
Ankit Kumar 4 years, 11 months ago
Manyata Joshi 4 years, 11 months ago
Posted by Santhosh Kumar 4 years, 11 months ago
- 4 answers
Nandani Singh 4 years, 11 months ago
Yogita Ingle 4 years, 11 months ago
AAS stands for Angle-angle-side. When two angles and a non-included side of a triangle are equal to the corresponding angles and sides of another triangle, then the triangles are said to be congruent.
Students sometime may get confused AAS with ASA congruency. But remember that AAS is for non-included side whereas ASA is for included sides of the triangles.
If there are two triangles say ABC and DEF, then as per AAS rule:
∠B = ∠E
∠C = ∠F
AB = DE
Hence,
Δ ABC ≅ Δ DEF
Posted by Rashika Maithil 4 years, 11 months ago
- 3 answers
Ankit Kumar 4 years, 11 months ago
Santhosh Kumar 4 years, 11 months ago
Posted by Swayam Deep 4 years, 11 months ago
- 1 answers
Gaurav Seth 4 years, 11 months ago
If the plasma membrane ruptures or breakdown then the cell will not be able to exchange material from its surrounding by diffusion or osmosis. Thereafter the protoplasmic material will be disappeared and the cell will die.
Posted by Supriya Pal 4 years, 11 months ago
- 4 answers
Sania Khan 4 years, 11 months ago
C Abbi 4 years, 11 months ago
Supriya Pal 4 years, 11 months ago
Yogita Ingle 4 years, 11 months ago
Newton’s 1st law states that a body at rest or uniform motion will continue to be at rest or uniform motion until and unless a net external force acts on it.
Newton’s 2nd law states that the acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
F = ma
The Newton’s 3rd law states that for every action there is an equal and opposite reaction.
Posted by Khushbu Pandit 4 years, 11 months ago
- 2 answers
Yogita Ingle 4 years, 11 months ago
Osmosis can be defined as the movement of water molecules from a higher water concentration area to the area of less water concentration through a semipermeable membrane. In other words, it can be defined as the diffusion of water molecules through a semipermeable membrane. It is a special case of diffusion of water (High to low). For example, water in the roots of plants is transported through osmosis.
Diffusion is the net movement of molecules of a substance from a region of their higher concentration to a region of their lower concentration. Net movement means there are more molecules moving in one direction than in the opposite direction.
Example: Opening a bottle of perfume in a room will result in the gradual diffusion of the perfume from the region of higher concentration (the bottle) out into the room. Diffusion will continue until the perfume has a more or less uniform concentration throughout the bottle and room.
Posted by Khushbu Pandit 4 years, 11 months ago
- 2 answers
Rashika Maithil 4 years, 11 months ago
Rahul Dayanand 4 years, 11 months ago
Posted by Anurag Sonkar 4 years, 11 months ago
- 1 answers
Manyata Joshi 4 years, 11 months ago
Posted by Harsh Rajput 4 years, 11 months ago
- 0 answers
Posted by Shreyansh Sutariya 4 years, 11 months ago
- 1 answers
Gaurav Seth 4 years, 11 months ago
Means of spread of Infectious disease
1)Air-borne diseases:Microbial agents can move from an affected person to someone else through air.
It occurs through the little droplets thrown out by an infected person who sneezes or coughs.
Someone standing close by can breathe in these droplets, and microbes get chance to start a new infection.
For Example :Common cold, pneumonia, tuberculosis
2)Water-borne diseases:They can be spread through water.
If the excreta from someone suffering from an infectious gut disease such as cholers or amoebiasis gets mixed with drinking water used by people living nearby.
The cholera infected bacteria will enter new hosts through the water they drink and cause disease.
3)Sexually Transmitted diseases(Syphilis,AIDS):These diseases are transmitted by sexual contact from one partner to other.However these diseases are not transmitted by causal physical contact.
AIDS virus can also spread through blood to blood contact with infected people or infected mother to her baby during pregnancy or breast feeding.
4)Through vectors:Vectors are carrier of a disease or infection.
Many animals which live with us may carry disease.These animals carry infecting agents from a sick person to another host.
Posted by Aditya Pratap Singh 4 years, 11 months ago
- 5 answers
Posted by Aditya Pratap Singh 4 years, 11 months ago
- 2 answers
Posted by Palak Pandey 4 years, 11 months ago
- 3 answers
Yogita Ingle 4 years, 11 months ago
It is the ability of an atom to gain or lose electron in order to achieve the noble gas configuration. It refers to the ability of an element to combine with other element. It is obtained by determining the number of electrons in the outermost shell (also called valence shell) of each atom of an element. For instance, sodium has 1 electron in its outermost shell and hence valency of sodium is 1.
Posted by Abhinandan Dubey 4 years, 11 months ago
- 2 answers
M U 4 years, 11 months ago
Gaurav Seth 4 years, 11 months ago
There are three states of matter – solid, liquid and gas.
- Solid: Matters which have fixed volume and shape are called solids. ...
- Liquid: Matters which have fixed volume but indefinite shape are called liquids. ...
- Gas: Matters which have indefinite shape and volume are called gases.
Posted by Abhinandan Dubey 4 years, 11 months ago
- 5 answers
Dhruv Kumar Jha 4 years, 11 months ago
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