Topics
Force, Work, Power and Energy
Work, Power and Energy
Machines
Force
Light
Refraction of Light Through Plane Surface
Spectrum
Refraction of Light Through a Lense
Sound
Electricity and Magnetism
Current Electricity
Electrical Power and Energy and Household Circuits
- Concept of Electrical Power and Household Circuits Numericals
- Household Circuits - Colour Coding of Wires
- Household Circuits - Three-pin Plugs
- Household Circuits - Safety Precautions
- Earthing (Grounding)
- Fuses
- Electric Switch
- Household Circuits – Main Circuit
- Electrical Energy and Power
- Electric Power
- Alternating Current (A.C.) Generator
- Current Electricity
- Resistors in Series
Electro Manetism
Heat
Modern Physics
notes
Uniform Motion:
A body is said to be in uniform motion if it travels equal distances in equal intervals of time, no matter how small these time intervals may be. If we draw distance time graph for uniform motion then it will be straight line. For better understanding we can take an example, a car is running at a constant speed say 20 metres per second, will cover equal distances of 20 metres, every second, so its motion will be uniform.
Non-Uniform Motion:
A body is said to be in a non-uniform motion if it travels unequal distances in equal intervals of time. For example, if we drop a ball from the roof of a tall building, we will notice that it will cover unequal distances in equal intervals of time. Like, 5 metres in the 1st second, 15 metres in the 2nd second and so on. Thus, a freely falling ball will covers smaller distances in the first ‘1 second’ and larger distances in the later ‘1 second’ intervals. Therefore, we can say that the motion of a freely falling body is an example of a non-uniform motion. The distance-time graph of the non-uniform motion is a curved line. Non-Uniform motion is also known as accelerated motion.
Basis of difference |
Uniform Motion |
Non-Uniform Motion |
Definition or meaning |
When a body moves along a straight line with uniform speed or steady speed is called Uniform motion |
When a body moves along a straight line but with variable or change in speed is called non-uniform motion |
How much distance is covered? |
Covers equal distance in equal intervals of time |
Covers unequal distances in equal intervals of time |
What is average speed here? |
Same as the actual speed of the object |
Different from actual speed of the object |
Rectilinear motion |
Acceleration is zero |
Acceleration is non-zero |
Distance-time graph |
Here distance-time graph shows straight line |
Here distance-time graph shows curved line |
notes
Uniform Circular Motion:
When an object moves in a circular path with uniform speed, its motion is called uniform circular motion.
In our everyday life, we came across many examples of circular motion for example cars going round the circular track and many more. Also earth and other planets revolve around the sun in a roughly circular orbits
If the speed of motion is constant for a particle moving in a circular motion still the particles accelerates because of constantly changing direction of the velocity.
If an object moves in a circular path with uniform speed, its motion is called uniform circular motion
Here in circular motion, we use angular velocity in place of velocity we used while studying linear motion.
Force which is needed to make body travel in a circular path is called centripetal force.
We know that the circumference of a circle of radius r is given by 2πr. If the body takes t seconds to go once around the circular path of radius r, the velocity v is given by
`"v"="2πr"/"t"`