unit 1 - kinematics

Question 1

How do forces influence the motion of an object?

Answer 1

Forces cause changes in the state of motion, either by initiating movement, altering speed, or changing direction

Question 2

Define Instantaneous speed

Answer 2

Distance travelled by a body in a very short interval of time

Question 3

How does a distance-time graph depict an object’s speed

Answer 3

by the object’s slope

Question 4

What is terminal Velocity/Speed

Answer 4

A constant velocity with which a body falls down under the influence of gravitational force and fluid resistance

Question 5

Frictional force?

Answer 5

The force that opposes relative motion and exists due to irregulates present between surfaces

Question 6

If there is no applied force acting on a body, the frictional force will be

Answer 6

ZERO

Question 7

Frictional force will continue to increase with increase in

Answer 7

applied force

Question 8

What role does air resistance play in the motion of objects?

Answer 8

Air resistance prevents the motion of objects through the air, affecting their speed and trajectory.

Question 9

Value of frictional force =

Answer 9

Value of applied force

Question 10

What is normal reaction, purpsoe and direction?

Answer 10

Force acting on a body when its present on top of a surface. Does not exist if the body is not present on a surface

Purpose is to stop the body from falling through the surface

Direction is always perpendcular to the surface

Question 11

What is gravitational force?

Answer 11

Gravitational force is the attraction between objects with mass, pulling them toward each other.

Question 12

What is a restoring force?

Answer 12

Force developed within any material which is elastic in nature and that always acts to pull a body back toward equilibrium

Question 13

What is mass equilibrium?

Answer 13

Point where spring force and gravitational force is the same

Question 14

Hooke’s Law

Answer 14

Within the elastic limit, the restoring force is directly proportional to the displacement of the body, from its equilibrium position.

Question 15

What is tension

Answer 15

Force which is transmitted through a rope, chain, wire when pulled by forces acting on opposite sides

Question 16

Hooke’s Law equation

Answer 16

F = -kx (F = restoring force, -k = Spring constant, x = Displacement from equilibrium position)

Question 17

What is static friction?

Answer 17

Friction that acts on objects that are at rest. Increases with applied force and has a max possible vlaue

Question 18

What is dynamic friction?

Answer 18

present between two objects which are in relative motion. this value is less than static friciton.

Question 19

Why does firction exist?

Answer 19

Irregularities between the objects and surface. There is oging to be an interlock

Question 20

dynamic friction is also known as

Answer 20

Kinetic friction

Question 21

Why does the statsic friction drop after reaching limiting friction when force is applied?

Answer 21

Because the objects starts moving and kinetic friction takes over

Question 22

What is the max possible value of static friction called?

Answer 22

Limiting Friction, when the applied force exceeds this value, the body starts to move.

Question 23

Disadvantages of friction

Answer 23

Can cause unnesscary wear and tear
Wastes some energy in the form of heat and possibly sound

Question 24

importance of friction in motion

Answer 24

Helps maintain necessary traction between objects
Provides grip in certain needed situation

Question 25

What is momentum. Unit and type of quantity

Answer 25

Product of Mass and Velocity, vector quantity, SI unit - kgms^-1

Question 26

What is the law of inertia or Newton's first law

Answer 26

A body continues to remain in a state of rest or in a state of motion until & unless an external force acts on it

Question 27

What is Newton's second law

Answer 27

The acceleration of a body is directly proportional to the force applied and indirectly proportional to its mass

Question 28

What is Newton's third law

Answer 28

For every action there is an equal and opposite reaction if action is on one body, the reaction will be on the other

Question 29

what is the law of conservation of momentum?

Answer 29

For an isolated system of objects, the momentum before collision is equal to the total after the collision

Question 30

What is a force

Answer 30

Described as a push and pull on an object interacting with another object

Question 31

Effect of force on an object

Answer 31

1. Start or end motion 2. Change an object's shape/size 3. Change direction of motion

Question 32

What happens when an object is balanced in terms of moments

Answer 32

The Anticlockwise moment is equalt o the clockwise moment arounda a common pivot

Question 33

Define moments/torque in physics

Answer 33

The rotational turning effect caused by a force on a body on its axis on a pivot point

Question 34

What is a pivot

Answer 34

the point at which the lever is supported and around which it rotates

Question 35

To get the biggest moment possible, what 2 things could you do?

Answer 35

1. Increase the distance from the pivot 2. Increase force applied

Question 36

If the input & output force are on different sides of the pivot, then they will act in which direction?

Answer 36

different directions to each other

Question 37

If the input & output force are on the same sides of the pivot, then they will act in which direction

Answer 37

same direction to each other

Question 38

What is Impulse, SI unit and its 2 formulas

Answer 38

Change in momentum Si unit = Ns formula = I = F * Δt I = mv - mu

Question 39

How is pressure defined and calculated in a physics context?

Answer 39

pressure is the perpendicular force present per unit area calculated by a ratio perpendicular force (F) over an area of cross-section (A) P = F/A

Question 40

What to do is force applied isnt perpendicular when calculating pressure

Answer 40

Find the component of force which is perpendicular and assume that and calculate using that

Question 41

Pressure and area are what type of relationship

Answer 41

inversely related (pressure increases, area decreases)

Question 42

What is collisions

Answer 42

2 objects are said to collide with each other if there is a change in the state of motion of one object because of the other

Question 43

What is Inelastic collisions?

Answer 43

Kinetic energy is not conserved and is transformed into other forms of energy after the collision. Both objects move in same direction

Question 44

What is density, what is the unit and what formula to calculate it

Answer 44

Amount of mass present per unit volume P = Mass/Volume Unit = kgms^-3

Question 45

Work definition and formula

Answer 45

Work is said to be done is a force displaces an object in the direction of the force applied. W = Force * displacement W = Force * displacement * cos θ

Question 46

Power defination and formula

Answer 46

Rate at which work is done P = Work done/time P = (Force * displacement)/time P = force * velocity

Question 47

Equation of best fit line formula for desmos

Answer 47

y1 ~ mx1 + b

Question 48

Weight

Answer 48

force exerted on an object due to its gravity Mass can never change, but weight can change W = mg

Question 49

Escape velocity

Answer 49

Minimum velocity required to escape a planet's gravitational field

Question 50

Spring constant

Answer 50

its a measure of how stiff or rigid a spring is. It tells us how much force is needed to stretch or compress a spring by a certain distance. A higher value would mean a more sitffer string and a lower value would mean a loose string

Question 51

Work-energy theorem

Answer 51

Work done can be represented as change in KE

Question 52

When is fluid resistance equal to weight of a body and why

Answer 52

Fluid resistance equals to the weight of the body when the he object reaches terminal velocity. This is because at terminal velocity the acceleration of the body must be 0 (body falls with constant speed) hence the net difference between the forces must be 0. Hence fluid resistance equals to weight of body