CBSE Updates

• Read newspaper daily. 
• Watch youtube videos on news clippings. 
• Download a short 1-minute video. 
• Write the text and try to speak in that manner. 
• Record your voice and listen. 
• Compare it with the newsreader and try to improve. Do a lot of reading. 
• Make a friend with whom you talk in English. 
• Read one article daily for 10 to 15 minutes. 
• Watch youtube for programmes like Toastmasters, Ted Talks.
• Stand in front of the mirror and give a two-minute speech every day.

Follow these tips, and you will observe a significant improvement.

Our Solar System consists of 8 planets, i.e. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus & Neptune. Let us learn some terms used in the solar system like a celestial body, planet, asteroid, meteoroids etc.

1. Celestial Body - Those body shinning in the night are called the celestial body, ex-Sun, Moon, Star
2. Planets - Those objects which do not have their light are called planets, ex - Earth, Venus
3. Orbit - All the eight planets move around the sun in an elongated path called an orbit.
4. Asteroids - These are tiny particles move around the sun other than star, moon etc.
5. Meteoroids - These are small pieces of rocks that move around the sun.
6. Satellite - It is a celestial body that moves around the planet. It can be natural like the moon and manufactured.

Various important points should be adopted while you are on the way to hole your English Speaking. 

Let me explain some most essential factors.

1. Speaking: Speaking carries a lot of weight in speaking. You have to speak much as you can. You can talk with everyone you find to talk to.
2. Build up Vocabulary: As English is not your native language. We need words to explain ourselves, our thoughts and whatever we have inside. So ofcourse we need words to express ourselves.
3. Listening: Listening will help the students improve their ways to pronounce words and listening skills.
4. Think in English: To Achieve fluency in English, we need to think in English. Mostly we make this mistake while speaking English and struggle to get fluency.

 
Frame of reference:
When the position of a particle in space changes with time, it is said to be in motion. To describe motion, a frame of reference is needed first and foremost. The set of spatial coordinates (x, y, z) and time t describe the position of a particle at a particular time t with respect to the frame of reference, which is the aforesaid coordinate system. A clock that is not in motion with respect to that frame of reference can measure proper time in that frame. So the particle moving with velocity v with respect to one frame of reference(R1) might be at rest with respect to another frame of reference(R2) while R2 is moving with respect to R1 with velocity v.
Thus we conclude that motion is a relative phenomenon, and to describe motion, a frame of reference is always needed.
There are two types of frame of reference. A frame of reference that does not have acceleration and rotation is called an inertial frame of reference. All inertial frames move with respect to one another with constant velocity. Most importantly, the laws of Physics( including Newton's laws of motion) hold and are the same in all inertial frame of reference. This statement can not be made in the case of an accelerating or rotating frame. There, to express Newton's equation of motion, one must introduce pseudo forces that solely arise due to acceleration and/ or rotation of the frame.

Example 1:

A force of 1200 N acts on the surface of area 10 cm² normally. What would be the thrust and pressure on the surface?

Given:

Force F = 1200 N, Area A = 10 cm² = 10 ×10^-4 m² = 10^-3 m²

Thrust = Normal pressure = F = 1200 N

Pressure P = F/A 1200N10−3m21200N10−3m2
              
                      = 1.2 ×× 10⁶ N/m²

Example 2:

The elephant weighs 20,000 N stands on one foot of area 1000 cm². How much pressure would it exert on the ground?

Given:

Force applied by elephant F = 20,000 N, area A = 1000 cm² = 1000/100×100m² = 0.1 m²

The pressure is given by

Pressure P = F/A

      = 20,000N/0.1m2

        = 2,00,000 N/m².

Example 3:

Calculate the pressure produced by a force of 800 N acting on an area of 2.0 m².

Solution:

Pressure is defined as force per unit area or P = F / A
P = (800 N) / (2.0 m2
)
P = 400 N / m2
= 400 Pa

Example 4:

The pressure of a gas contained in a cylinder with a movable piston is 300 Pa. The area of the piston is 0.5 m². Calculate the force that is exerted on the piston.

Solution

Pressure is defined as force per unit area or P = F / A
We multiply both sides of the equation by the area to solve for the force as
F = P A
F = (300 Pa) (0.5 m2
)
F = 150 (Pa) m2
= 150 (N / m2
) m2
F = 150 N

Example 5:

A swimming pool of width 9.0 m and length 24.0 m is filled with water to a depth of 3.0 m. Calculate pressure on the bottom of the pool due to the water.

Solution:

The pressure due to a column of fluid is calculated as the product of the height of the fluid times
the density of the fluid times the acceleration due to gravity. For water the density is d = 1000 kg /
m3
.
? P = d h g
? P = (1000 kg / m3
) (3.0 m) (9.8 m / s2
)
? P = 29400 kg m2 / m3
s2
To simplify the units we cancel one m term in the m2
term in the numerator and one m term in
the m3
term in the denominator to get
? P = 29400 kg m / s2
m2

We know that 1N = 1 kg m / s2
so we can write
? P = 29400 N / m2
= 29400 Pa