Thursday, July 30, 2009

Assignment 2 IX

Q1 Two balls of A and B of masses m and 2m are in motion with velocities 2v and v respectively.calculate the ratio of their momenta.

Q2 Two bodies A and B of sane masses are moving with velocities V and 3V respectively. Compare their a) inertia b)momentum c) the force needed to stop them.

Q3 The speed of car weighing 1500 kg increases from 40m/s to 50m/s. calculate the change in its momentum. (Ans 15000 kgm/s)

Q4 Name the property of the material bodies which resist any change in their state of rest or of uniform motion.

Q5 State two factors that determine the momentum of the body.

Q6 Newton's first law is also called law of inertia. why?

Q7 Give the direction of the magnitude and direction of the net force acting on
A) a drop of rain falling down with a constant speed
B) a cork of mass 10g floating on water.
C) a kite held stationary in the sky.

Tuesday, July 28, 2009

QUERIES



Dear students ,

Its been really good to see some of you, having new experience, feeling the concept of blogs and trying to access it and look into new vision.
I am creating this new label, QUERIES. Whenever you want to inquire something from me and want to advice me, you can post your queries in the form of comment. I would reply you back on the same.

All you need is to click on the label queries, and click on add comment.It will open a window , select google account from any profile( make sure you are logged in through google account) and your comment will be published

Issac Newton





* Sir Issac Newton was one of the greatest scientists. As a boy , he ofetn made mechanical devices such as a model of windmills and water clocks.

* with his theory of gravity, he discovered that the universe is held together .

* Newton discovered and entirely new branch of science called Calculus.

* He also doscovered that sunlight is a mixture of all colours.

* His greatest acgievement was his laws of motion.

* He also invented a kind if telescope that is now standard for astronomers.

Monday, July 27, 2009

Electricity


*Electric Current
An electric current is defined as the amount of charge flowing through any cross section of a conductor per unit time. I= Q/t.

* Electric current in terms of number of electrons(n) in a conductor , I= ne/t
e=1.6 x 10-19 C

* S.I unit of current is AMPERE(A).

* Ampere(A) Elevtric current through a conductor is said to be 1 ampere of one coulomb charge flows through any cross section in one second.

* Ammeter is uded to measure domestic circuits.

* Electric current is a scalar quantity.

*Electric potential is defined as work done per unit charge.
V= W/q

* S.I unit of electric potential is VOLT(V)

*Voltmeter is used to measure the potential difference between two points in an electric circuits.

* voltmeter is always connected in parallel in an electric circuits.

*Ohm's law
This law states that " electric current flowing in a conductor is directly proportional to the potential difference acreoss the ends of the conductor, provided the temperature and other physical conditions of the conductor remains the same."
V= I x R


* The graph for ohms law is a straight line.


Circuit of ohms law


* Resistance
It is the ability of the conductor to oppose the flow of charge through it.

* Unit of reistance is Ohm.

* Resistance of a conductor is said to be 1 Ohn if a potential differnce of 1 Volt across the ends of the conductor produces a current of 1 ampere through it.

* Laws of resistance
1) Depends on the nature of the material of the conductor.
2) Directly propirtional to the length of the conductor.
3) inversely proportional to the area of the cross section.
4) increases with temperature and decrease with decrease in temperature.

VINEGAR BATTERY

VINEGAR BATTERY



A zinc coated nail (2" galvanized nail) and length of copper wire (6 cm of 14 gauge copper wire) are suspended in vinegar (4% acetic acid). 
A discarded film container is ideal for this project .
The copper lead is the "+" terminal of the battery and the galvanized nail is "-".






Sunday, July 26, 2009

rocket car


ROCKET CAR

Objective: Newton's Third Law of Motion is demonstrated with escaping air as the action force.

Description: In this activity, students construct a balloon-powered rocket car that rolls across the floor because air is forced to escape through a plastic.

Materials and Tools:4 pins
Styrofoam tray
Cellophane tape
Flexi-straw
Scissors
Drawing compass
Marker pen
Small party balloon
Ruler

Procedure:

1. Using the ruler, marker, and drawing compass, draw a rectangle about 7.5 cm by 18 cm and four circles 7.5 cm in diameter on the flat surface of the tray. Cut out each piece.

2. Inflate the balloon a few times to stretch it. Slip the nozzle over the end of the flexi-straw nearest the bend. Secure the nozzle to the straw with tape and seal it tight so that the balloon can be inflated by blowing through the straw.

3. Tape the straw to the car as shown in the picture.

4. Push one pin into the center of each circle and then into the edge of the rectangle as shown in the picture. The pins become axles for the wheels. Do not push the pins in snugly because the wheels have to rotate freely. It is okay if the wheels wobble.

5. Inflate the balloon and pinch the straw to hold in the air. Set the car on a smooth surface and release the straw.

Saturday, July 25, 2009

interview with god







Provided by this Internet Marketing Online site.

Friday, July 24, 2009

Assignment 1 IX (uniform motion)

Q1 Draw a d-t graph for a ball at rest , when the ball is 4m away from the origin.

Q2 Draw a d-t graph of a ball which starts from rest and then its speed increases with time.

Q3 Draw a d-t graph for an object noving with constant velocity 2m/s2.

Q4 What does the speedometer of bus indicates?

Q5 Name the physical quantity that corresponds to rate of change of velocity.

Q6 Give one example of a uniform motion in a straight line in which velocity is chamging at unoform rate.

Q7 Give one example of a non - uniform motion in which acceleration is not constant.

Q8 Give an example of a motion in which the acceleration is in teh direction of motion.

Q9 Name the physical quantity which remains constant during uniform circular motion.

Q10 Name the physical quantity which changes during uniform circular motion.

force and laws of motion

BubbleShare: Share photos - Play some Online Games.

force and laws of motion


CHAPTER AT A GLANCE
1. Dynamics is the study of the motion of bodies while taking onto account the cause of motion ie force.
2. force is an agent whose action can produce acceleration in a body.
3. Inertia is the ability of a body be virtue of which it opposes any change in its state of rest or uniform motion.
4. The inherent property of a body by virtue of which it cannot change its state of rest is called INERTIA OF REST.
5.The inherent property of a body by virtue of which it cannot change its state of motion is called INERTIA OF MOTION.
6.The inherent property of a body by virtue of which it cannot change its state of direction is called INERTIA OF direction.


NEWTON"S FIRST LAW OF MOTION
It states that "An object at rest stays at rest or an object in motion, stays in motion (in the same direction/at the same speed) unless acted upon by an unbalanced force."
Also called the law of inertia


MOMENTUM
The total quantity of motion possessed by the body is called momentum.

Mathematically, momentum is Calculated by: P = mv
(p = momentum, m = mass, v = velocity)

NEWTON"S SECOND LAW OF MOTION

It states that" The rate of change of momentum is directly proportional to the applied unbalanced force in the direction of force."

Mathematically, F= m x a

Gravitational unit of force is Kilogram force(Kgf)

1 Kgf = 1 kg x 9.8 m/s2
= 9.8 N
NEWTON"S THIRD LAW OF MOTION

It states that " To every action there is an equal and opposite reaction"

A SINGLE ISOLATED FORCE DOESNT EXIST IN NATURE.

EFFECTS OF FORCE
1. Can produce motion in stationary bodies.
2. Can Stop a moving body.
3. Can change the speed and direction of the moving body.
4. can bring about change in the dimensions of the moving body.

FORCE DIAGRAM

Your pictures and fotos in a slideshow on MySpace, eBay, Facebook or your website!view all pictures of this slideshow

Wednesday, July 15, 2009

look- see - observe

look- see - observe
Of all the boundaries that the nature has endowed us with, perhaps the most important are the eyes. It is through our eyes that we come face -to -face with other bounties of nature. Eyes not only light-up -our lives, these also enlighten us .We see through our eyes. seeing is believing: so goes the saying.
But can you differntiate between looking , seeing and observing?
For this , first read what fedrick langbridge(1849-1923) has to say on this:
"Two men look out through same bars;
one sees the mud, and one the stars."
(taken from 'A cluster of quote thoughts)
One sees the mud is merely looking, one sees the stars is observing. At a scene of murder, onlookers are merely seeing the mutilated dead body; an observing cop will be lookng for all the important clue- a broken button, or torn tatter or the like.
A scientist is also like an observing cop. He see's what no one can see.
So stop; look ; see ; observe ' and very soon you may find a change in your outlook.

eclipse

Slide Album: eclipse

Wednesday, July 1, 2009

ICT workshop in chandigarh


It was agreat delight being a part of it. me along with sarita and parminder enjoyed being together in each other company. It was good and would keep these memories ever with me.