Unit 3 - Forces

Question 1

Newton’s 1st Law of Motion

Answer 1

An object in motion or at rest will remain in motion or at rest until acted upon by an outside force

Question 2

Newton’s 2nd Law of Motion

Answer 2

Force = Mass x Acceleration

Question 3

Newton’s 3rd Law of Motion

Answer 3

• For every action there will be an equal or opposite reaction, all forces occur in pairs)
• Motion only occurs when forces are unbalanced

Question 4

A force is…

Answer 4

A push or a pull (action) that has the ability to change motion

Question 5

Forces can…

Answer 5

Increase/decrease the speed of a moving object

Change the direction in which an object is moving

Question 6

Causes of forces…

Answer 6

Muscles, moving matter, massive objects, etc.

Question 7

1 pound = ___ Newtons

Answer 7

4.448 Newtons

Question 8

1 pound = ____ Kg

Answer 8

0.454 Kilograms

Question 9

Forces in the same direction…

Answer 9

Add them

Question 10

Forces in the opposite direction…

Answer 10

Subtract them

Question 11

Weight Formula

Answer 11

Weight = Mass x Gravity (9.8m/s/s)

Question 12

Weight and Mass…

Answer 12

• ARE NOT THE SAME
• Mass = amount of matter
• Weight = force (measured in Newtons)

Question 13

Sliding Friction

Answer 13

2 Solids

Question 14

Rolling Friction

Answer 14

Less resistance than sliding friction because of less contact with the surface area

Question 15

Fluid Friction

Answer 15

Fluid is anything with the ability to flow

Question 16

Momentum (p) Formula

Answer 16

Momentum (P) = Mass (M) x Acceleration (A)

Question 17

When an object is at equilibrium, the net force =

Answer 17

net force = 0 (no new movement)

Question 18

Normal Force is when…

Answer 18

when forces are balanced evenly

Question 19

Even if you’re going 20 mph on a roundabout, you’re still constantly accelerating because…

Answer 19

you’re constantly changing direction.