Circular Motion

Question 1

Define Circular Motion

Answer 1

Motion that is resulted from a net force perpendicular to the direction of motion

Question 2

Angular Speed

Answer 2

The rate of change in angular displacement with respect to time

Question 3

Linear speed

Answer 3

The rate of change of linear displacement with respect to time when motion is in a straight path

Question 4

Angular displacement

Answer 4

The change of angle as it rotates

Question 5

Tangential speed

Answer 5

The speed of an object moving along the circumference of a circular path

Question 6

Radian

Answer 6

The angle subtended at the centre of a circle by an arc equal in length to the radius of the circle

Question 7

Why does the speed of an object in circular motion not change?

Answer 7

The net force is directed perpendicular to the
Direction of motion (the velocity), this means that there is no work done by this force
W=F x cosX cos90=0

Question 8

What are the conditions of uniform centripetal force?

Answer 8

1. Has to be perpendicular to velocity
2. Has to have constant velocity

Question 9

What is rotational system and linear(translational) system and what is considered circular motion?

Answer 9

1.rotational system rotates about an axis through the system
2.linear system moves about an axis outside the system
3.rotational system describe path of C.M in terms of angles and looks at the motion from centre

Question 10

What are the changes quantities in the four equations?

Answer 10

S = angle
V = angular velocity
A = angular acceleration

Question 11

Centripetal Acceleration

Answer 11

Caused by a centripetal force of constant magnitude
That also acts perpendicular to the direction of motion in the centre

Question 12

Oscillation

Answer 12

A repeated back and forth movement on either side of some equilibrium position
-when object stopped it will return to equilibrium

Question 13

Forced oscillation properties

Answer 13

1.constantly applied force
2.frequency depends of force

Question 14

free oscillation

Answer 14

1.requires force to initiate only
2.frequency only depends on the nature of oscillation(natural frequency)

Question 15

Frequency

Answer 15

Number of oscillations in unit time

Question 16

Phase

Answer 16

The point that an oscillating mass has reached within one complete cycle

Question 17

What are properties of simple harmonic motion

Answer 17

1.the magnitude of acceleration and displacement are proportional to one another
2.the directions of acceleration and displacement are opposite to one another
3.period and amplitude are constant
4.period/frequency is independent of amplitude
5.displacement, velocity and acceleration are all sinusoidal functions in time
6.mass that oscillates and a position where it is equilibrium
7.have a restoring force that acts to return mass to equilibrium

Question 18

Force field

Answer 18

Region in the space where mass/charge/magnet pole experiences force

Question 19

Radial field

Answer 19

Field lines converge towards the centre of mass

Question 20

Newton’s universal law of gravitation

Answer 20

Force between two point masses is directly proportional to the product of the two masses and inversely proportional to square of the separation of the masses

Question 21

Field strength

Answer 21

Force experienced by a unit mass at a given point

Question 22

Gravitational potential energy

Answer 22

GPE of a mass at a point is the amount of work done in bringing the mass from infinity

Question 23

Gravitational potential

Answer 23

The GP at a point is the work done to bring a unit mass from infinity

Question 24

Damping

Answer 24

When oscillating system loses energy to the surrounding which results in decreasing amplitude

Question 25

Critical damping

Answer 25

The condition in which the damping of an oscillator causes it to return as quickly as possible to its equilibrium position without oscillating back and forth about this position

Question 26

Over damping

Answer 26

The condition in which damping of an oscillator causes it to return to equilibrium without oscillating; oscillator moves more slowly toward equilibrium than in the critically damped system

Question 27

Under damping

Answer 27

The condition in which damping of an oscillator causes it to return to equilibrium with the amplitude gradually decreasing to zero; system returns to equilibrium faster but overshoots and crosses the equilibrium faster but overshoots and crosses the equilibrium position one or more times

Question 28

Resonance

Answer 28

A phenomenon in which frequency of externally applied periodic force equals the natural frequency of the system, resulting in oscillation in largest possible amplitude

Question 29

What are some advantages of resonance

Answer 29

1. Microwave-resonating water molecules with EM wave at freq of natural freq of H20
   2.MRI(magnetic resonance Imaging)

Question 30

What are some disadvantages of resonance

Answer 30

Earthquakes resonating buildings

Question 31

What happens to resonance graph during damping?

Answer 31

-overall amplitude will decrease, curve below original
-Net gain of energy is less, flatter peak
-resonance frequency decreases, shifted peak to the left

Question 32

Simple harmonic motion

Answer 32

Acceleration proportional to displacement and directed towards a fixed point

Question 33

Natural frequency

Answer 33

The unforced frequency of oscillation of a freely oscillating object