Vectors

Question 1

Physical quantity

Answer 1

A measurement of something

Question 2

Speed equation

Answer 2

Distance (m)/ Time (sec)

Question 3

What is always on the x-axis

Answer 3

Time

Question 4

How to find the displacement of a velocity time graph?

Answer 4

The area under the velocity time graph gives displacement

Question 5

Upthrust/ buoyancy is a force cause by…

Answer 5

Pressure

Question 6

In a free fall diagram what is not taken into account

Answer 6

Air resistance

Question 7

What does upthrust depend on?

Answer 7

The density and volume of the liquid

Question 8

When firing a projectile what are the horizontal and vertical speeds?

Answer 8

Horizontal speed stays constant

Vertical speed is only affected by gravity (and therefore has an initial velocity of 0)

Question 9

For thinking distance, what is speed directly proportional to?

Answer 9

The distance
d=vt
v=d

Question 10

For braking distance, what is speed directly proportional to?

Answer 10

Initial velocity squared

s=u^2

Question 11

What are three methods you can use to measure acceleration due to gravity?

Answer 11

• Using a timer and ball
• Using 2 light gates (A and B)
• Using an electromagnetic timer

Question 12

What does the mass of an object depend on?

Answer 12

The amount of matter it contains (density)

Question 13

A net (resultant) force acting on an object will…

Answer 13

Make the object accelerate in the direction of the net force.
F=ma

Question 14

Mass

Answer 14

kg

It’s always constant for a specific object or particle

Question 15

Weight

Answer 15

Nkgms-2

Magnitude is variable (as depends on the location, gravitational field strength)

Question 16

What’s the equation for weight

Answer 16

W=mg

Question 17

What’s the value of g for an object during free fall

Answer 17

9.81m/s2

Question 18

How can you determine the weight of an object

Answer 18

Use a Newtonmeter which is calibrated to show the gravitational force acting on an object in Newtons.

Question 19

Centre of gravity

Answer 19

Where the weight appears to act from

Question 20

When is the centre of gravity equal to the centre of mass

Answer 20

When we are in a uniformed gravitational field

Question 21

When does an object become unstable?

Answer 21

As soon as the centre of mass is off the base

Question 22

Centre of mass

Answer 22

Defined as the point where the mass is centred (the point has no turning effect)

Question 23

How do you find the centre of mass for an irregular 2D object?

Answer 23

Use a plumb bob, which makes a plumb line, that tells you the direction gravity is acting (downward direction)

Question 24

Moment

Answer 24

The turning effect of a force

Question 25

Where would a moment act?

Answer 25

Around a pivot

Question 26

Which direction can a moment act?

Answer 26

Clockwise or anti-clockwise

Question 27

Moment equation

Answer 27

Moment= force x perpendicular distance to the line of action from the force

Nm= N x m

Question 28

In moments when is the object in equilibrium

Answer 28

When the forces and moments are balanced

F1d1=F2d2

Question 29

Couple definition

Answer 29

Is defined as 2 equal and opposite forces acting on a body but on different lines of action

Question 30

Torque

Answer 30

The moment produced by a couple

Question 31

When does an object topple over?

Answer 31

When its weight is outside its base

Question 32

What does stability depend on?

Answer 32

The width of the base

The height of the centre of mass

Question 33

Unstable equilibrium

Answer 33

Push an object (apply a force) and it won’t return back to its original position

Question 34

Stable equilibrium

Answer 34

An object will return back to its original position