# Dynamics Flashcards

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1
Q

Name Scalars

A

Speed
Distance
Mass
Time
Energy

2
Q

Name Vectors

A

Velocity
Displacement
Weight
Force
Acceleration

3
Q

What is a scalar?

A

Scalars are quantities defined by their size/magnitude only.

4
Q

What is a vector?

A

Vectors are quantities which are defined by their size/magnitude and direction.

5
Q

A

Nose to tail.

6
Q

How do you calculate the average speed?

A
1. Measure the distance between a and b
2. Measure the time taken to travel between a and b
3. Use v = d/t
7
Q

How do you calculate the instantaneous speed?

A
1. Measure the length of the card/trolley
2. Measure the time taken for the card/trolley to travel through the light gate
3. Use v = d/t
8
Q

What is the acceleration?

A

The acceleration is the rate of change of velocity.

9
Q

What does 5ms-2 mean?

A

The velocity is increasing by 5ms-1 every second.

10
Q

What does -3ms-2 mean?

A

The velocity is decreasing by 3ms-1 every second.

11
Q

How do you measure the distance/displacement from a velocity/time graph?

A

Find the area under the graph.

12
Q

How do you calculate the acceleration?

A

a = v - u / t

13
Q

What can a force change?

A

The speed, direction or shape of an object.

14
Q

What is the force that acts down on a object called?

A

Weight or the force of gravity.

15
Q

What is the force that always acts against a moving object?

A

Friction.

16
Q

What is the force in a stretched rope or wire called?

A

Tension.

17
Q

What is the definition of gravitational field strength?

A

The force of gravity per unit mass.

18
Q

What can be used to decrease friction?

A
1. Making the surfaces smooth
2. Separating the surfaces using lubricant.
3. Streamlining the objects.
19
Q

What is Newton’s 1st law?

A

An object will remain stationary or travel at a constant speed unless acted on by an unbalanced force.

20
Q

What is Newton’s 2nd law?

A

if the forces on an object are unbalanced an object will accelerate or decelerate.

21
Q

What is Newton’s 3rd law?

A

For every action there is an equal but opposite reaction.

22
Q

What is meant by a terminal velocity?

A

Air friction = weight

23
Q

Why does a projectile take a curved path?

A

A constant horizontal velocity.
A constant vertical acceleration.