Lesson 1: Newton's Law of Motion

Question 1

what is momentum?

Answer 1

the measure of motion of a body

Question 2

1. what is the formula for calculating momentum?
2. what does ‘m/s’ mean

the units as well!

Answer 2

1. momentum (kg m/s) = mass (kg) x velocity (m/s)
2. metres per second

Question 3

what is the symbol formula for calculating momentum?

Answer 3

p = mv

Question 4

what is force measured in?

Answer 4

newtons (N)

Question 5

what is newton’s first law of motion? :O

Answer 5

that a body will remain at rest or stay at a constant speed (velocity) unless a resultant force acts upon it!

Question 6

what is the force that always points downwards?

CONTEXT: on a diagram showing force

Answer 6

weight (from gravity)

Question 7

what are the 3 types of resistive force?

Answer 7

friction, water resistance and air resistance!

Question 8

what is the contact/reaction force called when underwater or partially underwater?

Answer 8

buoyancy/upthrust or water resistance

Question 9

what is water resistance? hmmm…

AND INCLUDE AN EXAMPLE ASWELL>:)

Answer 9

water resistance is the collision of water molecules/particles (e.g. water molecules colliding against a submarine which kinda slows it down, and opposes the thrust force!!

Question 10

what is buoyancy?

Answer 10

upwards force that is exerted by a liquid or gas on an object floating in the liquid or gas. can also be called upthrust hehe :D

Question 11

what are the different forces that point upwards?

♡⸜(˶˃ ᵕ ˂˶)⸝♡

Answer 11

hmmm- upthrust/buoyancy (underwater) or contact/reaction force

Question 12

when does a reaction/contact force happen?

Answer 12

it happens when two objects are in contact with eachother (e.g. a human and the floor). the human will be pushed down by weight (gravity) onto the floor however the floor will then push up (contact force): thats why humans dont floor through the floor lmao

Question 13

when does a reaction/contact force happen?

Answer 13

it happens when two objects are in contact with eachother (e.g. a human and the floor). the human will be pushed down by weight (gravity) onto the floor however the floor will then push up (contact force): thats why humans dont floor through the floor lmao

Question 14

when does upthrust occur?

Answer 14

when an object is partially or completely underwater upthrust will occur which is when the bottom surface of an object experiences a greater pressure than on the top surface. this results in a resultant force upwards. which is called upthrust/buoyancy!

Question 15

what is the conservation of momentum?

Answer 15

total momentum before collision = total momentum after collision
momentum MUST always be conserved!!

Question 16

calculate momentum:
p = ? m = 80kg v = 20m/s

Answer 16

p = m x v
p = 80kg x 20m/s
p = 1600kg m/s
ANSWER: 1600kg m/s
well doneeee:)

Question 17

calculate:
p = 120kg m/s m = ? v = 60m/s

Answer 17

p = m x v (rearrange)
p/v = m
120kg m/s / 60m/s = 2kg
AMSWER = 2kg !!
well done again hehe

Question 18

calculate:
p=150kgm/s m=15kg v=?

Answer 18

p = m x v
150kg m/s = 15kg x v
p/m = v
150/15 = 10m/s
ANSWER = 10 m/s !

Question 19

calculate
p=? m=20kg v=13m/s

Answer 19

p = m x v
p = 20kg x 13m/s
p = 260kg m/s
260kg m/s

Question 20

calculate:
p=15kg m/s m=5kg v=?

Answer 20

p = m x v
p/m = v
15/5 = 3m/s
v = 3m/s
ANSWER = 3m/s

Question 21

calculate:
p=8000 kg m/s m=100kg v=?

Answer 21

p = m x v
p/m = v
8000/100 = v
80m/s = v
ANSWER = 80m/s