Dynamics

Question 1

Name Scalars

Answer 1

Speed
Distance
Mass
Time
Energy

Question 2

Name Vectors

Answer 2

Velocity
Displacement
Weight
Force
Acceleration

Question 3

What is a scalar?

Answer 3

Scalars are quantities defined by their size/magnitude only.

Question 4

What is a vector?

Answer 4

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

Question 5

How are vectors added?

Answer 5

Nose to tail.

Question 6

How do you calculate the average speed?

Answer 6

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

Question 7

How do you calculate the instantaneous speed?

Answer 7

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

Question 8

What is the acceleration?

Answer 8

The acceleration is the rate of change of velocity.

Question 9

What does 5ms-2 mean?

Answer 9

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

Question 10

What does -3ms-2 mean?

Answer 10

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

Question 11

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

Answer 11

Find the area under the graph.

Question 12

How do you calculate the acceleration?

Answer 12

a = v - u / t

Question 13

What can a force change?

Answer 13

The speed, direction or shape of an object.

Question 14

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

Answer 14

Weight or the force of gravity.

Question 15

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

Answer 15

Friction.

Question 16

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

Answer 16

Tension.

Question 17

What is the definition of gravitational field strength?

Answer 17

The force of gravity per unit mass.

Question 18

What can be used to decrease friction?

Answer 18

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

Question 19

What is Newton’s 1st law?

Answer 19

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

Question 20

What is Newton’s 2nd law?

Answer 20

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

Question 21

What is Newton’s 3rd law?

Answer 21

For every action there is an equal but opposite reaction.

Question 22

What is meant by a terminal velocity?

Answer 22

Air friction = weight

Question 23

Why does a projectile take a curved path?

Answer 23

A constant horizontal velocity.
A constant vertical acceleration.