Question

Names of 15 physical quantites.

-with definitions
- with S.I unit
- Other units

Answer 1

●Mass - It is defined as the matter occupied by a body, denoted by M, It is a fundamental physical quantity.

SI unit is kg
cgs unit is grams.

●Time .
it is the fundamental unit in physics. Is the basic physical unit and most of other units are derived from this. it is denoted by T in most cases. sometimes by n. Ex. distance travelled in nth second.

SI and cgs units both are second .

●Electric current - it is defined as the charge flowing through a substance(conductor) per unit time, It is denoted by I


Si unit is Ampere or coulomb/sec.
cgs unit is biot .

● speed - it is defined as distance covered per unit time ,denoted by v,it is a scalor quantity.

SI unit is m/s
cgs is cm/s

● velocity - it is defined as displacement per unit time. it is denoted by v, it is a vector quantity.

si unit is m/s
cgs is cm/s

● Acceleration - it is defined as change in velocity per unit time.
There are two kinds of acceleration +ve and - ne
acceleration.
When acceleration is in direction of motion then acceleration is +ve
when acceleration is in opposite direction of motion then it is called -ve acceleration(also known as retardation)
It is a vector quantity.


Si unit is m /s^2
cgs is cm/s^2

●Force - it is defined as product of mass and acceleration. It is a vector quantity.

F=ma

Si unit is kg-m/s^2 (Newton)
cgs is g-cm/s^2(dyne)

● Pressure- it is defined as force per unit area.
P = F/A
In fluids pascals law is a principle in fluid mechanics that states that a pressure change occurring anywhere in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere.

Si unit is pascal. or (Newton/m2)

cgs is Dyne/cm2

● work- it is defined as force × displacement
It is actually dot product of force and displacement and is defined by
W= F.ds or W= FScos(○)

si unit is Newton - s
cgs is Dyne -s

● density -it is defined as mass per volume
it can be also defined as the degree of compactness of a substance.
Density of water is assumed to be most at 4°c.
si unit is kg/m3
cgs is g/cm3

● area - Extent of a surface

Si unit is m2
cgs is cm3

●Angular velocity -The angle incremented in a plane by a segment connecting an object and a reference point per unit time.

it can be also defined as The rate of change of angular position of a rotating body.

It is denoted by w(omega)
It is given by w= d○ /dt
where d○ is small radian .

Si unit is radian/s

● Torque-Product of a force and the perpendicular distance of the force from the point about which it is exerted.
It is denoted by t(tou)
and given by t = l×F
it is cross product of Force and length AXis of rotation from center of rotation.

Its SI unit is - N-m
cgs is dyne -cm.

●Weight .-Amount of gravitation force exerted on an object.

Si unit is Newton.
Cgs is Dyne .

● Volume -The three dimensional extent of an object.
Si unit is m3
cgs is cm3.

Sorry for randomness.

Hope you will like it.

Answer 2

Hello friend,

Here is your answer -

<>Temperature- The intensity of heat present in an object and expressed in comparative scale, shown by the thermometer or Our body temperature above the normal one or The inside heat present in a human body.


-SI unit of temperature is Kelvin

-Other unit of temperature is Celsius, and faranheit.

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<>Mass [M] - Mass is the measure of resistance of a body to acceleration when net force is applied on it. But some people think mass and weight is same, but it is not, {as on moon our weigh is 1/80th of the mass on earth,but still mass remains the same. So mass and weight has a difference.

SI unit of mass is kilograms (kg).

Other units of mass is

-grams,
-slug
-pounds,
-Tonnes

And some more.

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<> Speed (v) - Speed is a scalar quantity. Speed of a moving object is the distance travelled by it in unit time. ie- Speed = Distance/time.

Speed are of 4 types -

^Uniform speed - If an object covers equal distances in equal intervals of time, the speed of an object is said to be uniform speed.

^Non-uniform speed- if an object covers unequal distances in unequal interval of time or equal distance in unequal intervals or time or unequal distances in equal intervals of time, then the speed of the object is known as Non-uniform speed.

^Average speed- the total distance divided by total time taken is average speed of a object.

^Instantaneous speed- The speed of an object at particular instant during its motion is called instantaneous speed.

SI unit of speed is metre per second (m/s).
In CGS system, the speed is used to be measured in cm/sec.

Other units of speed -

-km/hr
-mi/hr [miles/hour]

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<> Velocity (v) - It is a a vector quantity. Velocity of an object is its speed moving in particular direction. Or we can define it as displacement of object in per unit time. ie- velocity- displacement/time.

SI unit of velocity- m/s.
In CGS system it is cm/s.

And If the object is moving, we usually express the velocity in km/h.

Other units of velocity-

-m/s
-km/h

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<> Acceleration- Acceleration is too a vector quantity as it has both magnitude and direction mentioned.

Acceleration is of 2 types-

^Uniform acceleration- if an object travels in straight line and it's velocity changes in equal amounts and in equal intervals of time then the acceleration of the object is in uniform.

^Non-uniform Acceleration- if the velocity of the object doesn't change by unequal amounts in equal intervals of time then the acceleration is said to be Non-uniform.

SI unit of acceleration- m/s^2
In CGS system - cm/s^2

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<>Volume- we can say that volume is the amount of space that is occupied by a 3-D object. Or in other definition, volume is the loudness of sound.

SI unit of volume- litre (l)

Other units of volume are-

-ml
-gallons
-pint

And some more.

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<> Force- Force is the external push or pull which can change the state of rest to motion or motion to rest or to change the direction of the object. A force can also change the shape or size of an object.

Force is of 2 types-

^Balanced force- When a number of forces act simultaneously on any object do not produce any changes on object then the force is said to be in balanced force.

^Unbalanced force- When 2 or more force act at same time on any object and changes the state of rest then the motion is said to be in unbalanced force.

Hope it helps...!!

Please I will answer the rest in 2 hrs. Thanks!!