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Ask QuestionPosted by Trishla Jain 4 years, 11 months ago
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Posted by Sourav Singh 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
- Thomson’s model revealed that atom has spherical structure, with positive charge spread all over the sphere and electrons are embedded in it. Also there is equal number of positive and negative charge i.e. atom is electrically neutral.
- Ernest Rutherford carried out experiments by taking consideration in Thomson’s model and presented more accurate model i.e. Rutherford’s model. Rutherford bombarded ⍺ particles i.e. He2+ ions on gold foil. Gold foil has very thin thickness of about 1000 atoms thick. Observations of Rutherford’s experiment are
- Most of ⍺ particles passes through gold foil
- Some ⍺ particles get deflected with very small angles from their path
- Very few i.e. 1/ 12000 were reflected back on same path
On basis of observations, Rutherford put forth conclusion
- Most ⍺ particles pass through gold foil, therefore, atom must have large empty space in it.
- Some ⍺ particles gets deflected, hence there is some strong dense opposition. ⍺ particle is positively charge. If ⍺ particle is deflected then, opposition must be having a positive charge.
- Very few ⍺ particles are deflected this shows that, positive and other mass of atom is in very small volume in the atom.
- Moreover, it was identified that radius of dense space is 105 times smaller than size of atoms.
Posted by Arun Kushwah 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
There is no comparison between diffusion and tissue. So mention some points may help you to understand Diffusion and tissue.
- Diffusion is the process of movement of molecules under a concentration gradient.
- It is an important process occurring in all living beings. Diffusion helps in the movement of substances in and out of the cells.
- The molecules move from a region of higher concentration to a region of lower concentration until the concentration becomes equal throughout.
- Liquid and gases undergo diffusion as the molecules are able to move randomly.
Tissue
- A group of cells that are similar in structure and work together to do a peculiar function is called tissue.
- Tissues provide structural strength, mechanical strength, show division of labour.
- The use of tissues in multicellular organisms is to provide structural and mechanical strength as well as to allow division of labour.
Posted by Anjali Rao 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
A quantity which has only magnitude but no direction is known as a scalar quantity.
Work is done only when a force produces motion.And it is the product of the force exerted on the the body and the distance moved by the body in the direction of force.
i.e. W =F.s
Work is actually the scalar product of force and displacement and hence is a scalar quantity.
W =F.s
i.e. W = Fs cos θ
where F is the force, s the displacement and θ the angle between force and displacement. According to the angle θ, work can be positive, negative, or zero.
Work is the outcome of the force and displacement caused by the body.
Force and displacement are vector quantities (they have both magnitude and direction) and the dot product of two vector quantites always gives a scalar quantity. So work has only magnitude but not direction.
Posted by Sourav Singh 4 years, 11 months ago
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Meghna Thapar 4 years, 10 months ago
Kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity.
Derivation:
Let us consider an object of m which is at rest lying on a table.
Let A force F acts on the object which moves the object through a distance S.
The workdone=F×S
W=Fnet×S-------(1)
Let the work done on the object causes a change in its velocity from u to V and let a be the acceleration.
From Third equation of motion:
V²−u²=2as
s=V²−u²/2a----------(2)
By Newton's Second law:
F=ma------(3)
From equation (1), (2) and (3)
W=ma×(V2−u2/2a)=(1/2)m(V2−u2)
As we assumed object at rest, u=0
W=(1/2)mV2
we know that the kinetic energy of a body moving with a certain velocity is equal to work done on the object to acquire that velocity from rest.
∴K.E=1/2mV2
Posted by Tamana Yadav 4 years, 11 months ago
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Pavleen Bagga 4 years, 11 months ago
Anjali Rao 4 years, 11 months ago
Posted by Rimjhim Paroche 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
Mass of an object= the gravitational constant/ weight of the object.
The mass of an object whose weight in 196n is going to be 19.6 kg if the gravitational constant is taken to be 10g.
And it is 20 kg, in case the gravitational constant is taken to be 9.8 g.
Posted by Palak Pandey 4 years, 11 months ago
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Anjali Rao 4 years, 11 months ago
Yogita Ingle 4 years, 11 months ago
An isotope of cobalt is used in the treatment of cancer.
An isotope of iodine is used to treatment of goiter.
Posted by Hriday Saha 4 years, 11 months ago
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Gaurav Seth 4 years, 11 months ago
Answer:
The cells formed by meristematic tissue take up a specific role and lose their ability to divide. As a result, they form a permanent tissue. This process of taking up a permanent shape, size and function is called differentiation.
Posted by Komal Bhullar 4 years, 11 months ago
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Anjali Rao 4 years, 11 months ago
Gaurav Seth 4 years, 11 months ago
A n s w e r :
The work done will be zero because a coolie carries a load make an angle of 90 degree wherever the 90 degree created the work done will be zero
Posted by Hriday Saha 4 years, 11 months ago
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Gaurav Seth 4 years, 11 months ago
In desert plants, rate of water loss gets reduced due to the presence of cuticle.
The epidermis of the desert plant has a thick layer of cutin that is called cuticle. It is a waxy layer present on the leaves whose primary function is to reduce the water loss from the plant.
Posted by Hriday Saha 4 years, 11 months ago
- 1 answers
Meghna Thapar 4 years, 10 months ago
Goblet cells derive their name from their goblet, cup-like appearance. They arise from pluripotent stem cells. The primary function of goblet cells is to secrete mucin and create a protective mucus layer. Regardless of fixation, goblet cells have a distinctly polarized morphology. Their nucleus is at the base of the cell, along with organelles such as mitochondria, endoplasmic reticulum and Golgi. The remainder of the cell is filled with membrane-bound secretory granules filled with mucus.
Posted by Hriday Saha 4 years, 11 months ago
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Posted by Hriday Saha 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
Sclerenchyma tissue found in the stem, root and many other parts of the plant, is made up of dead cells.
Posted by @Sanjivani ☺️☺️ 4 years, 11 months ago
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Posted by Krishna Mishra 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
| * It is defined as the force of attraction between two objects of unit mass each separated by unit distance. | * It is defined as the acceleration of an object freely falling under the action of force of gravity. |
| * Universal constant and its value is 6.673×10-11Nm2kg-2. | * Constant at a given place and its value changes from place to place. Mean value of g on surface of earth is 9.8 ms-2. |
Posted by Keshav Maratha 4 years, 11 months ago
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Posted by 《Aruba》°°° 《Sayed》❤ 4 years, 11 months ago
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Meghna Thapar 4 years, 10 months ago
Average power is defined as the ratio of total work done by the body to the total time taken by the body. The unit of average power is kiloWatt hour. It is the average amount of work done or energy converted per unit of time. The average power is often simply called "power" when the context makes it clear. The instantaneous power is then the limiting value of the average power as the time interval Δt approaches zero.
Posted by 《Aruba》°°° 《Sayed》❤ 4 years, 11 months ago
- 2 answers
Posted by 《Aruba》°°° 《Sayed》❤ 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
The law of conservation of energy states that energy can neither be created nor be destroyed. Although, it may be transformed from one form to another. If you take all forms of energy into account, the total energy of an isolated system always remains constant. All the forms of energy follow the law of conservation of energy.
Posted by Rr Rudrapratap 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
While doing cooking, generally we add salt to vegetables ( contains water).
Adding salt, makes the concentration of salt higher in outside membrane of vegetables than in inside. ( more salt, less water)
As a result, due the process of OSMOSIS, water from vegetables comes outside making it softer and helps in faster cooking.
Posted by Sakshi Tomar 4 years, 11 months ago
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Posted by Rr Rudrapratap 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
Plasmolysis is defined as the process of contraction or shrinkage of the protoplasm of a plant cell and is caused due to the loss of water in the cell. Plasmolysis is an example of the results of osmosis and rarely occurs in nature.
The word Plasmolysis was generally derived from a Latin and Greek word plasma – The mould and lusis meaning loosening.
Posted by Rr Rudrapratap 4 years, 11 months ago
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Ananya K 4 years, 11 months ago
Posted by Yogesh Jangid 4 years, 11 months ago
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Posted by Sneha Prajapat 4 years, 11 months ago
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Yogita Ingle 4 years, 11 months ago
Colloidal solution is a heterogeneous mixture of two or more substances. Colloidal solutions appear homogenous because of relatively small size of particles in comparison with suspension. Particles of colloidal solution are called colloid. Colloids are dispersed throughout the solvent. Particles of colloidal solution are not visible through naked eye but scatter the ray of light, i.e. show Tyndall effect. Colloids cannot be separated by filtration but can be separated using centrifugation.
Posted by Keshav Maratha 4 years, 11 months ago
- 4 answers
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Gaurav Seth 4 years, 11 months ago
We wear cotton clothes during summer as cotton absorbs sweat from the body, exposing to the atmosphere for easy evaporation. As we tend to sweat more during summer and cotton fabric absorbs sweat and help body to cool down. Cotton allows better air circulation which helps to absorb and removing body moisture caused by sweat via evaporation.
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