Unit 1

Question 1

Physics is the…

Answer 1

Basic of all sciences. Its concepts are the foundation for all other sciences.

Question 2

Mathematics is important to science because…

Answer 2

It gives a simple way to express complex relationships. It is unambiguous.

Question 3

Difference between science and technology.

Answer 3

Science is a method of answering questions. Technology is a method of solving problems.

Question 4

Fact

Answer 4

a close agreement by competent observers who make a series of observations of the same phenomenon

Question 5

Law or Principle

Answer 5

A hypothesis that has been tested over and over again and is not contradicted

Question 6

Theory

Answer 6

a synthesis of a large body of information that includes well-tested and verified hypotheses

Question 7

Physics

Answer 7

The study of the nature of things such as motion, forces, energy, matter, heat, sound, light, and the composition of atoms

Question 8

Why are equations often used in science?

Answer 8

Because they provide guides to thinking. They don’t have double meanings and provide a common language for the discussion of ideas.

Question 9

Five general steps of the scientific method?

Answer 9

1. Identify the problem.
2. Create a hypothesis (an educated guess) about the answer.
3. Predict the consequences of the hypothesis.
4. Perform experiments to test your predictions.
5. Formulate the simplest general rule that organizes the hypothesis, prediction, and experimental outcome.

Question 10

1kg=

Answer 10

10N

Question 11

10N=

Answer 11

2.2lbs

Question 12

Vector quantity

Answer 12

A vector quantity is a quantity that describes both magnitude and direction.

Question 13

Equilibrium rule

Answer 13

Whenever the net force on an object is zero, the object is said to be in mechanical equilibrium.

Question 14

Two forces acting on a book at rest on a table

Answer 14

The weight of the book due to gravity acts downward. The support force provided by the table acts upward on the book.

Question 15

Force

Answer 15

A push or pull on an object. Unit of force is N (newtons of gravity force).

Question 16

Net force

Answer 16

The combination of all acting forces

Question 17

When is something in equilibrium?

Answer 17

If an object moves at constant speed in a straight line then it is in equilibrium

Question 18

Inertia is a way to measure…

Answer 18

how hard it is to change an object’s motion.

Question 19

Mass

Answer 19

a measure of the amount of matter in an object. Unit of mass is kg.

Question 20

Weight

Answer 20

A measure of the force of gravity on an object.

Question 21

Equation relation to weight and mass.

Answer 21

Weight = mass * acceleration due to gravity. W=mg

Question 22

Equation Newton’s second law of gravity

Answer 22

F=ma

(force = mass * acceleration). [kg * m/s^2]

Question 23

m/s^2 =

Answer 23

N/kg

Question 24

Newton’s first law.

Answer 24

Law of Inertia. A body in motion tends to remain in motion if no net force is exerted on the body in the direction of motion.

Question 25

Copernicus's idea

Answer 25

He thought that Earth and the other planets moved around the sun.

Question 26

What did Galileo explain?

Answer 26

that a force is not necessary to keep an object moving

Question 27

Friction

Answer 27

The force that acts between materials that touch as they move past each other. Irregularities in the surface that the object is touching obstructs motion and causes friction, which opposes motion.

Question 28

What is a measure of inertia?

Answer 28

Mass. The more mass an object has, the more inertia it has and the more force is needed to change the state of motion.

Question 29

A hypothesis must be...

Answer 29

testable. If it cannot be proven or disproven, it is outside the realm of science.

Question 30

Tension

Answer 30

Stretching force

Question 31

Scalar quantity

Answer 31

Can be described by magnitude only and has no direction.

Question 32

Support force

Answer 32

Upward force that balances weight of an object on a surface. aka normal force.

Question 33

Resultant

Answer 33

Sum of 2+ vectors

Question 34

Acceleration

Answer 34

Means speed up, slow down or change direction. The rate at which velocity changes. Acceleration is around 10m/s^2 moving upwards, 9.8m/s^2 moving downwards

Question 35

Speed

Answer 35

How fast something freely falls from rest after an elapsed time. Has both scalar and vector quantities.

Question 36

Equation for falling in free fall (distance)

Answer 36

d = 1/2*gt^2. g=10m/s^2

Question 37

Change in position

Answer 37

Motion

Question 38

Change in motion

Answer 38

speed, velocity (w/ directional information)

Question 39

Instantaneous speed

Answer 39

the speed at any instant.

Question 40

Free fall

Answer 40

When an object moving under the force of only gravitational force

Question 41

Elapsed time

Answer 41

The time passed since the beginning of any motion.

Question 42

The instantaneous speed of an object at its highest point after it is thrown straight up into the air

Answer 42

zero

Question 43

Distance

Answer 43

how far an object has fallen

Question 44

Relative

Answer 44

when an object moves in motion with respect to the other object.

Question 45

Speed equation

Answer 45

speed = distance/time. v = d/t

Question 46

Average speed

Answer 46

ave. speed = (total distance covered)/(time interval)

Question 47

Velocity

Answer 47

Speed in a given direction

Question 48

Acceleration equation

Answer 48

acceleration = change of velocity/time interval

Question 49

instantaneous speed equation

Answer 49

instantaneous speed = acceleration * elapsed time. v = gt

Question 50

Vertical Direction velocity

Answer 50

(change in)y = v(0) + 1/2(a(y)t^2))

Question 51

Horizontal direction change

Answer 51

(change in)x = v(0)t + 1/2(a(x)t^2))

Question 52

Displacement

Answer 52

``` s = v(i)(change in)t + (a(change in)t)^2/2 s = distance ```