Linear and Angular Motion

Question 1

Linear Motion:

How do you calculate displacement?

Answer 1

Displacement= final position- initial position
(m)

Question 2

Linear Motion:

How do you calculate velocity?

Answer 2

Velocity= change in displacement/ time
(m/s)

Question 3

Linear Motion:

How do you calculate acceleration?

Answer 3

Acceleration= change in velocity/ time
(m/s2)

Question 4

What are the four main SUVAT equations?

Answer 4

s: displacement
u: initial velocity
v: final velocity
a: acceleration
t: time taken

v= u + at
v2= u2 + 2as

s=ut+ 1/2 at2
s= 1/2 (u+v) t

Question 5

EG: if a trampolinist was in the air for two seconds, how high did they go?

Answer 5

s: ANSWER?
u: initial velocity= 0
v: final velocity?
a: acceleration= 9.81
t: time= 1 (half of full time)

s= ut + 1/2 at2
s= 1/2 at2
s=0.5 x 9.81 x 12
s= 4.9m

Question 6

What are the figures for vertical and horizontal force/ acceleration?

Answer 6

Vertical force: gravity
Vertical acceleration: -9.81

Horizontal force: 0
Horizontal acceleration: 0

Question 7

Linear motion:

How go you calculate linear momentum?

Answer 7

Momentum= mass x velocity
(kgm2)

Question 8

Angular momentum:

Translation vs Rotation?

Answer 8

Translation: through the middle/ force through a centre of mass/ direct force
= straight

Rotation: outside the centre of mass/ moves and rotates around the centre of mass
= rotation

Question 9

What are the three separate ways you can display a circle?

Answer 9

130 degrees = a circle

1 revolution/ 1 rev= a circle

2pie radians= 1 circle
1pie radian= 180 degrees

Question 10

How do you calculate degrees into revs and revs in degrees?

Answer 10

135 degrees into revs= DEVIDE BY 360

=135/360= 0.357 revs

0.357 revs into degrees= TIMES BY 360

=0.356 x360= 260 degrees

Question 11

Angular Motion:

How do you calculate angular velocity?

Answer 11

Angular Velocity= angular displacement/ time

AV= W

(rad/s)

Question 12

Angular Motion:

How do you calculate angular acceleration?

Answer 12

Angular acceleration= change in angular velocity/ time

(rad/s2)

Question 13

EG: when throwing a hammer an athlete rotates 360 degrees/ s and releases at 900 degrees/ s in 2.5 seconds, what’s the angular acceleration?

Answer 13

= change in angular velocity/ time

=900-360 / 2.5
=216 degrees/s2

Question 14

What is Moment of Inertia?

Answer 14

The rotational equivalent of mass
The resistance of a body to change its state of angular motion
Distribution of mass about an axis

AXIS= Longitudinal

Transverse

Frontal

Question 15

Angular Motion:

How do you calculate moment of inertia: (I)

Answer 15

Moment of Inertia= mass x radius from axis of rotation 2

I= mr 2

kgm2

Question 16

Angular Motion:

How do you calculate angular momentum? (H)

Answer 16

Angular momentum= angular velocity x moment of inertia

H= w x I

w= rad/s
I= kgm2

Angular momentum= kg/m2. s-1