Turning forces

• Science
• Lower Secondary (Key Stage 3)

Turning forces

The turning effect of a force is known as

1. Newtons
2. Rotation
3. Moment
4. Squashed

What is the name for a fixed point around which an object can turn

1. Pivot
2. Moment
3. Equilibrium
4. Gravity

When we multiple
force x distance from the pivot what are we calculating?

1. Moment
2. Friction
3. Turning speed
4. Force

When the anticlockwise rotations equal the clockwise rotations we say the object is

1. Broken
2. At rest
3. Accelerating
4. At equilibrium

What are all the green lines pointing to?

What are all the green lines pointing to?

1. Fulcrum
2. Handle
3. Pivot
4. Pilot

Name two things a moment's size depends on

Which moment is the largest

1. A
2. B
3. C

Which moment is the smallest

1. A
2. B
3. C

What is the point about which an object rotates called?

1. Hub
2. Center
3. Axis
4. Pivot

What is the turning force of an object around the pivot known as?

1. Force
2. Power
3. Torque
4. Moment

How can the rotation of an object be described?

1. Clockwise
2. Upward
3. Downward
4. Anti-clockwise

What factor determines the size of a moment?

1. Weight and speed
2. Force and distance from the pivot

What can forces cause an object to do, apart from rotating?

1. Illuminate, evaporate, expand, contract
2. Speed up, slow down, change direction, deform

List 6 everyday objects whose movement is caused by moments.

Suggest a reason why the see-saw is not rotating.

What two pieces of information do you need to calculate the magnitude of a moment?

1. Temperature in Celsius and time in seconds
2. Mass in kilograms and acceleration in m/s^2
3. Force in Newtons and perpendicular distance in metres
4. Voltage in volts and current in amperes

What is the equation to find the moment of a turning force?

1. moment (Nm) = Force (N) / perpendicular distance (m)
2. moment (Nm) = Force (N) - perpendicular distance (m)
3. moment (Nm) = Force (N) + perpendicular distance (m)
4. moment (Nm) = Force (N) x perpendicular distance (m)

What is the unit for moments?

1. Watt second (Ws)
2. Newton metre (Nm)
3. Joule per second (J/s)
4. Kilogram metre (kgm)

How does the value of Newton metres relate to the turning force?

1. Newton metres is a measure of distance, not force
2. The value of Newton metres has no relation to turning force
3. The greater the value of Newton metres, the smaller the turning force
4. The greater the value of Newton metres, the greater the turning force

If you increase the force acting on an object, what happens to the moment?

1. The moment decreases
2. The moment becomes negative
3. The moment increases
4. The moment remains the same

What does the law of moments state?

What is the condition for an object to be in equilibrium?

1. The sum of the anticlockwise moments is greater than the sum of the clockwise moments.
2. The sum of the clockwise moments is not related to the sum of the anticlockwise moments.
3. The sum of the clockwise moments equals the sum of the anticlockwise moments.
4. The sum of the clockwise moments is greater than the sum of the anticlockwise moments.

How can an object like a see-saw be in equilibrium?

1. By having only one person sat at any distance from the pivot.
2. By having two people of different mass sat at different distances from the pivot.
3. By having two people of different mass sat at an equal distance from the pivot.
4. By having two equal mass people sat at an equal distance from the pivot.

What happens if the clockwise and anticlockwise moments are not equal in size?

1. The object will remain in equilibrium.
2. The object will accelerate in a straight line.
3. The object will become lighter.
4. There will be rotation/movement and the object is not in equilibrium.

When is an object said to be in equilibrium?

What happens to a seesaw at equilibrium?

How can two people make a seesaw reach equilibrium?

Two different size people want to make a seesaw reach equilibrium, how can they do this?

What are moments measured in?