Physics Terms

Question 1

displacement

Answer 1

Change in position. How far an object is from its starting point.

Question 2

average speed

Answer 2

distance traveled along its path divided by the time it takes to travel this distance.

Question 3

Velocity

Answer 3

Is a vector. Has a magnitude (numerical value) and the direction in which it is moving.

Question 4

average velocity

Answer 4

displacement divided by time elapsed

Question 5

acceleration due to gravity

Answer 5

9.80 m/s^2

Question 6

scalars

Answer 6

a number and unit

Question 7

vectors

Answer 7

has direction and magnitude

Question 8

examples of scalars

Answer 8

mass, speed, distance

Question 9

examples of vectors

Answer 9

velocity, acceleration, momentum, weight

Question 10

inertia

Answer 10

tendency of a body to resist a change in its motion

Question 11

mass

Answer 11

the measure of inertia of a body

Question 12

weight

Answer 12

the force of gravity on a body

Question 13

force

Answer 13

Ts considered a push or a pull. It is a vector. An action that gives rise to an acceleration.

Question 14

Net Force

Answer 14

net force on an object is the sum of all forces acting on it

Question 15

What are the two types of forces?

Answer 15

Contact forces and Field forces.

Question 16

Which is stronger? kinetic friction or static friction?

Answer 16

Kinetic friction is weaker. It is easier to keep an object moving than to get it started.

Question 17

Horizontal

Answer 17

left to right or like the x-axis

Question 18

Vertical

Answer 18

up and down or like the y-axis

Question 19

What is the difference between static and kinetic friction? Which coefficient is generally larger?

Answer 19

Static friction is with an object not moving, kinetic friction is to keep an object moving. Static friction is generally larger.

Question 20

An object acted upon by a net force will always experience a _____, which means it will either _____ and/or _____.

Answer 20

acceleration; speed up, change direction, and/or slow down.

Question 21

Describe velocity, acceleration, and net force when an object is in translational (linear) equilibrium.

Answer 21

Velocity is constant
acceleration is zero
Net Force is zero

Question 22

Two objects moving together (pulled by a rope or pushing each other) share the same_____

Answer 22

acceleration

Question 23

The normal force is always _______ to the surface.

Answer 23

perpendicular

Question 24

perpendicular

Answer 24

an angle 90 degrees to another line or surface

Question 25

The friction force always ______ the motion (or the intent of motion) and is proportional to the ______ force.

Answer 25

Opposes Normal

Question 26

Given an object on an incline, list the components of its weight parallel and perpendicular to the plane.

Answer 26

Parallel: mg sin theta Perpendicular: mg cos theta

Question 27

While an object is in projectile motion with no air resistance...

Answer 27

The horizontal component of its velocity remains constant and the vertical component of the acceleration is equal to -g

Question 28

A ball is tossed vertically upward. When it reaches its highest point (before falling back downward) ...

Answer 28

The velocity is zero, the acceleration is directed downward, and the force of gravity acting on the ball is directed downward.

Question 29

What are the 2 types of forces?

Answer 29

There are two types of forces. Contact forces are the result of two objects touching one another. Examples of contact forces are applied forces, drag force, friction force, force normal, spring force and tension. Field forces happen even when two interacting objects are not touching one another. Examples of Field forces are gravitational force, magnetic force and electric force.

Question 30

Tension

Answer 30

Tension force or the force of tension (T or FT) is the force transmitted through a rope, cable, string or wire pulled taut by forces acting on both ends.

Question 31

Newton's Third Law

Answer 31

Newton’s Third Law states that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object

Question 32

Friction Force

Answer 32

The friction force is the force exerted by a surface as an object moves across it or makes an effort to move across it.

Question 33

Frictions Forces

Answer 33

Kinetic friction is weaker than static friction, as it is easier to keep an object sliding once it is sliding than to start an object sliding in the first place (Newton’s 1st law). Therefore, there are two types of µ, denoted with subscripts. For a given pair of surfaces, it is true that µk < µs.

Question 34

A projectile has no horizontal acceleration and so moves at a constant velocity in the horizontal.

Answer 34

true

Question 35

A projectile is in free fall, so its vertical acceleration is aways -10 m/s^2

Answer 35

true

Question 36

The vertical displacement of a projectile launched and landing at the same level is aways zero

Answer 36

true

Question 37

Forces at Angles

Answer 37

If the net force has both a vertical and a horizontal component, use the Pythagorean theorem to determine the magnitude of the net force, and use the tangent function to determine the direction of the net force.

Question 38

Object in Free fall

Answer 38

When an object is in free fall, its acceleration is 10 m/s per second10 toward the ground. “Free fall” means no forces other than the object’s weight are acting on the object.

Question 39

Projectile's horizontal acceleration

Answer 39

A projectile has no horizontal acceleration, and so it moves at constant speed horizontally. A projectile is in free fall, so its vertical acceleration is 10 m/s per second downward

Question 40

The horizontal and vertical motion charts for a projectile must use the same value for time.

Question 41

In a position-time graph, the object’s position is read from the vertical axis.

Question 42

In a position-time graph, the object’s speed is the slope of the graph. The steeper the slope, the faster the object moves. If the slope is a front slash (/), the movement is in the positive direction; if the slope is a backslash (\), the movement is in the negative direction.

Question 43

In a velocity-time graph, the object’s speed is read from the vertical axis. The direction of motion is indicated by the sign on the vertical axis.

Question 44

In a velocity-time graph, the object’s acceleration is the slope of the graph.

Question 45

In a velocity-time graph, the object’s displacement is given by the area between the graph and the horizontal axis. The location of the object can’t be determined from a velocity time graph; only how far it ended up from its starting point can be determined.