Mechanics

Question 1

Father of mechanics

Answer 1

Newton

Question 2

Father of modern physics

Answer 2

Max plankck
Medieval newton
Ancient galileo

Question 3

Kinematics

Answer 3

Motion of the body

Question 4

Dynamics

Answer 4

Motion of the body along with reasons

Question 5

Scalar quantities

Answer 5

Which has only magnitude but no direction
Vector has both mag and direction

Question 6

Vector quantities

Answer 6

Velocity displcement acceleration force impulse momentum weight torque

Question 7

Displcement

Answer 7

The shortest path between two points called displcement
Sometimes it will be negative or zero

Question 8

First law of equation

Answer 8

V= u + at
Equation descibes about velocity and time

Question 9

2 nd law of equation

Answer 9

S= ut+ 1/2 at2
It describes about time and position

Question 10

Third law of equation

Answer 10

It describes about the velocity and displcement

Question 11

Different masses are dropped from certain height which one reach first

Answer 11

All are reach at ssame time
Galileo
We can’t observe because air create disturb
In vaccum all are reach at a same time

Question 12

Newton first law

Answer 12

Law of inertia
Inertia at rest
Inertia at motion
Inertia at direction

Question 13

Newton second law

Answer 13

The amount of force applied on object is directly proportional to mass of the object and it’s acceleration
F= ma

Question 14

Momentum

Answer 14

Masa * velocity

Question 15

If it has mass and velocity

Answer 15

It has also momentum

Question 16

Conservative laws of linear momentum

Answer 16

Sum of momentum before collision is equal to sum of after collision
Without collision where we observe
Gun fire
Canon tank
Rocket motion
Bomb explosion
Bullet and wooden block

Question 17

Impulse

Answer 17

The large force acting on a body within short span of time
Nail with hammer
Axe to cut tree
Ball with bat
Hockey stick
Force * time cgs dyne sec
Impulse also called change in the momentum

Question 18

Reducing the impulse

Answer 18

Shock absorbers are used in the automobiles
Soft materials are filled in the long jump
Takes his hands back before catching the ball
Egg on bed
Mobile packing
Helmet wearing

Question 19

Newton third law

Answer 19

Every action there is also opposite reaction
Running. Swimming
Flying bird
Rocket. Missiles and jet flights

Question 20

Work

Answer 20

W = f * displacement
Product of Force and displacement
Nm - joule
Cgs dyne cm called erg

Question 21

One joule

Answer 21

10 to the 7 erg

Question 22

One newton

Answer 22

10 to the power 5

Question 23

If angle given between force and displacement

Answer 23

W= fscos@
Positive
Negative
Zero

Question 24

Positive work

Answer 24

Force and displacement are in same direction
Degree lies less than 90
Object kept above the surface of the earth
Koolie kept object
Bulb at some height
Pe =Mgh

Question 25

Negative

Answer 25

Force and displacement are opposite in direction Only obaerved in ramps

Question 26

Zero work

Answer 26

W=fscos@ If f= 0 w = 0 S zero work zero 90 work zero Railway cookie force and 90 so work is zero Carrying suitcase is also work zero

Question 27

Power

Answer 27

The rate of doing work Pani retunu called work P = work / time Si joule) / sec called James watt Invented steam engine Cgs unit erg / sec

Question 28

One hp

Answer 28

746 wats

Question 29

Energy

Answer 29

The capacity to do work is called energy Potential energy Kinetic energy Si unit joule

Question 30

Potential

Answer 30

The energy possessed by the body of it's position or place Stored energy Pe = mgh Strectched rubber Catball stored energy An arrow inthe bent bow Water stored in a reservoir A stone on the top of a mountain The ending point of the potential energy is the starting point of ke Raised hammer Raised axe Pounding rod Calling bell Compressed cycle bell

Question 31

Kinetic energy

Answer 31

The energy possessed by a body due to its motion 1/2 mv2

Question 32

The relationship between kinetic energy and linear momentum

Answer 32

P^2 /2m

Question 33

If the velocity of the body doublee then ke will be

Answer 33

Four times

Question 34

If the momentum of the body doublee then kinetic energy also

Answer 34

Four times

Question 35

If the velocity of the 1/3 then ke will be

Answer 35

1/9

Question 36

Mechanical energy

Answer 36

Aeroplane Kiye Clouds Rocket motion Flying bird

Question 37

Friction

Answer 37

Surface irregularity Roughness of the surface

Question 38

Advantages of a friction

Answer 38

Walking running writing Holding the things Ignition of match stick Breaking system

Question 39

Disadvantages of friction

Answer 39

Energy loss Wear and tear Depreciation Life span decrease

Question 40

How to overcome the friction

Answer 40

Polishing Lubricants Ball bearings Steam lining Graphite used as lubricant

Question 41

Drag

Answer 41

Friction due to fluids

Question 42

Centripetal

Answer 42

Sun and solar system exam ple of centripetal Gravitational force act as centrioetal Electirns revolve nuckess and acts as electrostatic force

Question 43

Centrifugal

Answer 43

Away from the centre Mixers Grinders Washing machine Butter seperated from the milk Seperation blood cells from the good Seperation of sugar crystals from molasis Seperation of honey from honey bee wax