Monday, 29 June 2020

CLASS 10 / PHYSICS / MAGNETIC EFFECTS OF ELECTRIC CURRENT / mind map + notes


MIND-MAP



NOTES
Magnet
The substances which have the property of attracting small pieces of iron, nickel and cobalt etc. are called magnets and this property of attraction is called magnetism.

Properties of magnet: 

  • Attracts objects of iron, cobalt and nickel.
  • Force of attraction of a magnet is greater at its poles then in the middle.
  • Like poles of magnets repel each other while unlike poles of magnets attract each other.
  • A free suspended magnet always point towards north and south direction.
  • The pole of a magnet which points toward north direction is called North Pole or north seeking.
  • The pole of a magnet which points toward south direction is called South Pole or south seeking.

Magnetic field

The space around a magnet in which the force of attraction and repulsion due to the magnet can be detected is called the magnetic field.

IMPORTANT NOTE:- Each point in the field of any magnet has a particular strength and magnetic field at each point has definite direction.
How do you find the direction of the magnetic field due to magnet at a point near it?
The direction of the magnetic field due to a magnet at a point near it can be found by placing a magnetic compass at that point.  The compass needle gets deflected when it is placed near the magnet.

Magnetic field lines

Imaginary lines used to represent magnetic field around a conductor/ magnet

 

Iron filings test around a bar magnet

Iron filings around a bar magnet exhibit the magnetic field lines that engirdle the bar magnet. The magnetic field lines can be explained as imaginary lines that graphically represents the magnetic field that is acting around any magnetic substance.

Properties of magnetic field lines
  1. All field lines are closed curves.
  2. Outside the magnet field lines emerge from North Pole and merge at South Pole.
  3. Inside a magnet, the direction of field lines is from South Pole to its north pole.
  4. Field lines never intersect each other.
  5. Field lines are closed together near the poles and spread out away from them.
  6. The field is stronger where the field lines are more closely spaced. So, the field is stronger near the poles then at other points.
Why do field lines never intersect each other?
If two lines were to intersect each other, then a compass needle placed at the point of interaction would point in two different directions which is not possible.

 


Magnetic Field Due to a Current Carrying Conductor


Electricity and Magnetism are related phenomenon. When an electric current is passed through metallic conductor, it generates a magnetic field around it.
 
Magnetic Field due to current through straight Conductor
Electric current through a straight Conductor generates magnetic field around it.
a)Magnetic Field intensity increases on the increasing the current in the conductor
b) Magnetic field decrease as the distance increase from the conductor
c) Magnetic Field direction can be find using Right Hand Thumb Rule
 
What is Right Hand Thumb rule?
When you are holding a current-carrying straight conductor in your right hand such that the thumb points towards the direction of current. Then your fingers will wrap around the conductor in the direction of the field lines of the magnetic field












CLASS 10 / MATHS / PAIR OF LINEAR EQUATION IN TWO VARABLE / mind map


CLASS 10 / MATHS / PAIR OF LINEAR EQUATION IN TWO VARABLE / exemplar problems

CLASS 10 / MATHS / POLYNOMIALS / exemplar problems

CLASS 10 / MATHS / POLYNOMIALS / 2019-20 board questions




CLASS 10 / MATHS / POLYNOMIALS / mind map


Wednesday, 22 April 2020

CLASS 9 / MATHS / LINES AND ANGLES / concept map + points to remember

CONCEPT MAP

POINTS TO REMEMBER
1. If a ray stands on a line, then the sum of the two adjacent angles so formed is 180° and vice-
versa. This property is called as the Linear pair axiom.

2. If two lines intersect each other, then the vertically opposite angles are equal.
3. If a transversal intersects two parallel lines, then
(i) each pair of corresponding angles is equal,
(ii) each pair of alternate interior angles is equal,
(iii) each pair of interior angles on the same side of the transversal is supplementary.
4. If a transversal intersects two lines such that, either
(i) any one pair of corresponding angles is equal, or
(ii) any one pair of alternate interior angles is equal, or
(iii) any one pair of interior angles on the same side of the transversal is supplementary,
then the lines are parallel.
5. Lines which are parallel to a given line are parallel to each other.
6. The sum of the three angles of a triangle is 180°.
7. If a side of a triangle is produced, the exterior angle so formed is equal to the sum of the two
interior opposite angles.

Sunday, 19 April 2020

CLASS 9 / MATHS / EUCLID'S GEOMETRY / points to remember


chapter -5, euclid’s geometry
Important points:
1.   Axioms or postulates are the assumptions which are obvious universal truths. They are not proved.
2.   Theorems are statements which are proved, using definitions, axioms, previously proved statements and deductive reasoning.
3.   Some of Euclid’s axioms were:
(i) Things which are equal to the same thing are equal to  one another.
(ii) If equals are added to equals, the wholes are equal.
(iii) If equals are subtracted from equals, the remainders are equal.
(iv) Things which coincide with one another are equal to one another
(v) The whole is greater than the part.
(vi) Things which are double of the same things are equal to one another
(vii) Things which are halves of the same things are equal to one another
4.   Euclid’s postulates were:
Postulate 1:
 A straight line may be drawn from any one point to any other point.
Postulate 2:
 A terminated line can be produced indefinitely
Postulate 3:
 A circle can be drawn with any centre and any radius.
Postulate 4:
          All right angles are equal to one another
Postulate  5 :
 If a straight line falling on two straight lines makes the interior angles on the same side of it taken together less than two right angles, then the two straight lines, if produced indefinitely, meet on that side on which the sum of angles is less than two right angles.
5.   Two equivalent versions of Euclid’s fifth postulate are:
(i)‘For  every  line  ‘l’ and  for  every  point  P  not  lying  on  ‘l’,  there exists  a  unique  line  m passing through P and parallel to ‘l’.
(ii) Two distinct intersecting lines cannot be parallel to the same line

CLASS 10 / PHYSICS / ELECTRICITY / worksheet 3


/ REVISION WORKSHEET / ELECTRICITY/ WORKSHEET 3


FOLLOW THE GIVEN LINK


https://prigupta.blogspot.com/2018/04/class-10-physics-revision-work.html

Saturday, 18 April 2020

CLASS 9 / MATHS / COORDINATE GEOMETRY / points to remember

class -9
chapter - 3
coordinate geometry

conept-map

Points to remember –
1.     If we take two number lines, one horizontal and one vertical, and then combine them in such a way that they intersect each other at their zeroes, and then they form a Cartesian Plane.
2.     The horizontal line is known as the x-axis 
3.     the vertical line is known as the y-axis.
4.     The point where these two lines intersects each other is called the origin. It is represented as ‘O’.
5.     The Origin has zero distance from both x-axis and y-axis so that its abscissa and ordinate both are zero. So the coordinate of the origin is (0, 0)
6.     A point on the x - axis has zero distance from x-axis so coordinate of any point on the x - axis will be (x, 0)
7.     A point on the y - axis has zero distance from y-axis so coordinate of any point on the y - axis will be (0, y)
8.     The Cartesian plane is dividing into four quadrants named as Quadrant I, II, III, and IV
9.     The x-coordinate and y - coordinate of the point in the plane is written as (x, y) for point and is called the coordinates of the point
10.The x - coordinate is also called the Abscissa.
11.The y - coordinate is also called the Ordinate.
12.The positions of both the points are different in the Cartesian plane
i.e  If x ≠ y, then (x, y) ≠ (y, x), and (x, y) = (y, x), if x = y.
13.The coordinates of the points in the four quadrants will have sign according to the below table



Friday, 17 April 2020

CLASS 10 / PHYSICS / ELECTRICITY / worksheet -2

CLASS 8 / MATHS / PLAYING WITH NUMBERS / worksheet

Class – VIII
SUBJECT – MATHS
Worksheet on playing with numbers




CLASS 9 / PHYSICS / MOTION / worksheet 1

CLASS -9
Chapter- MOTION
PHYSICS
WORKSHEET - 1

Multiple Choice Questions
1. A particle is moving in a circular path of radius r. The displacement after
half a circle would be:
(a) Zero
(b) π r
(c) 2 r
(d) 2π r
2. The numerical ratio of displacement to distance for a moving object is
(a) always less than 1
(b) always equal to 1
(c) always more than 1
(d) equal or less than 1
3. Which of the following figures (Fig. 8.3) represents uniform motion of a
moving object correctly?

4. In which of the following cases of motions, the distance moved and the
magnitude of displacement are equal?
(a) If the car is moving on straight road
(b) If the car is moving in circular path
(c) The pendulum is moving to and fro
(d) The earth is revolving around the Sun
A  m/s
B) ms
C) m/s2
D) none of these
A) zero
B) 24 m/s
C) 25 m/s
D) none of these
A) Speed
B) acceleration
C) Retardation
D) velocity
A) m/s
B) km/s
C) cm/s
D) none of these
A) m/s
B)m/s2
C) N s
D) N / s

A) πr
B) 2πr
C) 2r
D) 2π/r
Solve the following 
1.  An object cover a distance of 8 km in 2 minutes. Calculate the speed in:
(a)  m/s
(b) Km/h.

2.  Object A travelled a distance of 80 km in 4 hours and Object B travelled a distance of 100 km in 10 hours. Which object traveled faster?

3.  Arrange the following speeds in increasing order-
(a) Car moving with speed of 72 km/h
(b)  A kite moving with speed of 10 m/s
(c)  A train moving with speed of 1200 m/min

4.  What is the displacement travelled by a car if it takes 30 minutes for a journey with velocity 20 m/s.

5.  If a man walks at a speed of 2 km/h and walk a distance of 200 meters. How much time he will take to complete his walk?
6.  A bus decreases its velocity from 80 km/h to 60 km/h in 5 s. find the acceleration of the body.

7.  A train starting from a railway station and moving with uniform acceleration attains a speed 40 km/h in 10 minutes. Find its acceleration.

8.  A motor boat starting from rest on a lake accelerates in straight line at a constant rate of 3.00 m/sfor 8.0 s. how far does the boat travel during this time?

9.  A ball is gently dropped from a height of 20 m. if its velocity increases uniformly at a constant rate of 10 m/s2, .With what velocity will it strike the ground? After what time will it strike the ground?

10.  A bus starting from rest moves with a uniform acceleration of 0.1 m/s2 for 2 minutes. Find
(a) The speed acquired.
(b) The distance traveled.