Basic Concepts

 

Space

 

What is space, in the field of dynamics, and how do we usually define it?

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Space is the region occupied by the bodies under consideration.
Space is a vacuum.
Space is defined by a coordinate system.
Space is defined by its size.

 

 

 

 

Position

 

What is position and what are its units?

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Position identifies where a body is located in space and its units are length per time.
Position identifies where a body is located in space and its units are length.
Position identifies how fast a body moves from one place to another and its units are length per time.
Position identifies how fast a body moves from one place to another and its units are length.

 

 

 

 

Why do we need time in dynamics and what are its units?

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Rate of motion cannot be defined without time and the time units may be seconds.
Because motion variables usually depend on the time rate of change and the time units may be minutes.
It is important to know when and for how long an event occurs and the time units may be hours.
Variables that describe an object's motion are a function of time and the time units may be seconds.

 

 

 

 

Velocity

 

What is velocity?

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Velocity is the time rate of change of position.
Velocity is how fast a body is moving and in what direction.
Velocity is how fast a body is moving regardless of direction.
Velocity is the time rate of change of acceleration.

 

 

 

 

Is velocity a vector?

 

Yes
No

 

 

 

What are the units of velocity?

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m/s
m/s²
N
kg

 

 

 

Acceleration

 

What is acceleration?

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Acceleration is the time rate of change of position.
Acceleration is the time rate of change of velocity.
Acceleration indicates how fast a body is moving.
Acceleration is a measure of how fast or slow the velocity is changing.

 

 

 

 

Is acceleration a vector?

 

Yes
No

 

 

 

What are the units of acceleration?

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m/s
m/s²
N
kg

 

 

 

Force

 

What is force?

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Force is mass times acceleration.
A force is a push or pull that causes the velocity of an object with mass to change.
Force has magnitude and direction.
A force is non-directional.

 

 

 

 

Is force a vector?

 

Yes
No

 

 

 

What are the units of force?

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m/s
m/s²
N
kg

 

 

 

Mass and weight

 

What is weight?

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The quantity of matter in an object.
Weight is equal to mass.
Weight is mass time gravity.
The force that gravity exerts on a body.

 

 

 

 

What is mass?

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The quantity of matter in an object.
Mass is equal to weight.
Mass is weight divided by the acceleration due to gravity.
The force that gravity exerts on a body.

 

 

 

 

What are the two things that could make you weigh less?

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Go on a diet.
Weigh yourself on the moon.
Jump up and down on the scale.
Run really fast.

 

 

 

 

Is weight a vector?

 

Yes
No

 

 

 

Is mass a vector?

 

Yes
No

 

 

 

What are the units of weight?

Click all that apply.

 

m/s
m/s²
N
kg

 

 

 

What are the units of mass?

Click all that apply.

 

m/s
m/s²
N
kg