Stress: It is defined as the force applied on unit area to produce change in the shape,volume or length of a body.Mathematically it is expressed as: The SI unit of stress (σ) is newton per square meter (Nm-2),which is given the name pascal (pa). Stress may cause a change in length,volume and shape. Tensile stress: When a stress changes the ...

Read More »## Find angle between vectors?

Angle between two vectors: The angle between two vectors a and b is determined from the definition of dot product,that is: If θ = 0 or π then the vectors a and b are collinear. If θ = 90 then the vectors a and b will be perpendicular to each other. Example:Find the angle between the vectors. a = 2 i –j ...

Read More »## Properties of vectors

What is a vector ? Types of vectors Vectors scalar product Vector cross product How to find angle between two vectors? Vectors,both in plane and in space have following properties: Let u ,v and w be vectors in the plane or in space and let a,b ∈ R then they have the following properties: Commutative property u + v = v ...

Read More »## What is a vector ?

Difference between vector and scalar Vector scalar or Dot product Vector cross product Properties of vectors How to find angle between vectors? Types of vector What is vector in physics? Vector is defined as”The physical quantity which has magnitude and direction is called vector.”There are some physical quantities which required magnitude as well as direction for their complete description,such as ...

Read More »## difference between emf and potential difference

What is emf source? A source of electromotive force is a device in which non electrical energy is changed into electrical energy.Examples of e.m.f sources are electrical cells,thermocouples and generators. The e.m.f of the source is able to maintain its upper terminal positive and its lower terminal negative charge. When the switch is closed,the cell drives a clock wise current ...

Read More »## What is difference between spherical and chromatic aberration?

What is the meaning of aberration? The defect in the image formed by a lens or mirror,revealed as a blurring and possibly a false coloration,these principal aberrations are spherical aberrations,coma,and astigmatism. Aberrations occur when light rays do not pass close to optic axis of the system but make a considerable angle to it such that it is no longer accurate ...

Read More »## Difference between vector and scalar

What is scalar and vector quantity? The quantities having magnitude and unit is called scalar quantity.Some of these quantities have direction also but vector laws are not applied. Some examples of vector quantities are: Electric charge Mass distance current Speed Power The quantities which have magnitude,unit and direction are called vector quantities.These quantities also follow triangle law of addition.Some examples ...

Read More »## what are the common properties of electromagnetic waves?

Some common properties of all electromagnetic waves are: These waves are all the transverse waves. They travel with the same speed of light in vacuum but slow down in other medium such as glass and water. They are not required any medium to travel from one place to another place. They obey laws of refraction and reflection. These waves transfer ...

Read More »## What is difference between general and special relativity?

What is albert einstein’s theory of relativity? Theory of relativity is given by Albert Einstein in 1905 which states that there is no absolute state exist in the universe,all states are relative. Types of relativity: There are two types of relativity: General theory of relativity Special theory of relativity What is the general theory of relativity? It belongs to the ...

Read More »## what are the different types of nuclear reactions?

Nuclear Reactions: While studying radioactivity,we have seen that an α-particle is emitted from radium-226 and radon-222 is obtained. This nuclear is change is represented by the following equation: Such an equation represents a nuclear reaction. Above mentioned nuclear reaction takes place on its own accord. However, it was Rutherford who, first of all, expressed his opinion that besides natural radioactivity decay ...

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