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Question 1

inertia

Answer 1

The property of an object to resist changes in motion. is the resistance of any physical object to any change in its state of motion including changes to its speed and direction or the state of rest.

It is the tendency of objects to keep moving in a straight line at constant velocity.

Question 2

Newton’s first law of inertia

Answer 2

Every object continues in a state of rest or of uniform speed in a straight line unless acted on by a nonzero net force.

Key word is continues - if resting, continues to rest, if moving, continues to move without turning or changing speed

Question 3

force

Answer 3

a push or pull - gravitational, electrical, magnetic, muscular effort as source.

Question 4

net force

Answer 4

The vector sum of forces that act upon on object.

More than a single force acting on an object (think pushing from opposite sides, the difference in pressure is net force)

Question 5

newton

Answer 5

Unit of force. One newton is the force applied to a 1kg mass that will produce an acceleratioin of 1m per second per second. (9.8 newton = 1kg)

Question 6

vector

Answer 6

arrow that is drawn to scale used to represent a vector quantity

Question 7

vector quantity

Answer 7

Any quantity that has both magnitude and direction, such as force

Question 8

scalar quantity

Answer 8

A quantity that has magnitude only, not involving direction. (Mass, volume, speed)

Question 9

resultant

Answer 9

Sum (net result) of two or more vectors

Question 10

parellelogram rule

Answer 10

Used when vectors don’t act in exactly the same or opposite direction.

The diagonal of the parallelogram is the resultant. In the special case of two vectors that are equal in magnitude and perpendicular the parallelogram is square and the length of a diagonal is sq.of2 or 1.41 times one of the sides.

Question 11

tension

Answer 11

stretching force

Question 12

Mechanical equilibrium

Answer 12

The state of an object or system of objects for which there are no changes in motion. (Newton’s first law)

∑F = 0

∑ stands for “the vector sum of” and F is for forces.

This rule states that the forces acting upward on an object must be balanced by other forces acting downward to make the vector sum equal to zero.

Question 13

Support force

Answer 13

Also ∑F = 0, but in this case the upward force (maybe a table) and downward force of (a book) gravity equal 0. (the book lying on the table compressess atoms which behave like microscopic springs)

Question 14

Equilibrium rule

Answer 14

For any object or system of objects in equilibrium, the sum of the forces acting equals 0.

∑F = 0

Question 15

Equilibrium

Answer 15

A state of no change.

whether object is at rest or moving at a constant

Question 16

Speed

Answer 16

time  

How fast an object moves, distance traveled per unit of time.

Question 17

instantaneous speed

Answer 17

The speed at any instant

Question 18

velocity

Answer 18

An object’s speed and direction of motion

Question 19

Acceleration

Answer 19

 time interval  

The rate at which velocity changes with time; the change in velocity may be in magnitude, or direction, or both.

Question 20

velocity aquired

Answer 20

acceleration x time

v = gt

Question 21

free fall from rest

Answer 21

t10 t= time, 10 meters/sec velocity aquired every second

Question 22

Distance travelled

Answer 22

d = 1/2 g t2 (1/2 acceleration x time x time)

Question 23

Scientific method

Answer 23

1. recognize a question, puzzle, unexplained fact
2. make a hypothesis (guess) to resolve the puzzle
3. predict the consequences of the hypothesis
4. perform experiments or make calculations to test the predictions
5. formulate the simplest general rule that organizes the three main steps

Question 24

Law or principle

Answer 24

a hypothesis that has been tested repeatedly and has not been contradicted

Question 25

Theory

Answer 25

A synthesis of a large body of information that encompasses well-test and verified hypothese about certain aspects of the natural world.