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# KS3 Speed Pressure

### KS3 Speed Pressure and Moments

Question | Answer |
---|---|

What unit is used for the moments | the unit is N.m (N x m) |

When you jump out of a plane and you open your parachute, describe the forces on you and your speed after a few minutes opening it? | forces (air resistance and gravity) are balanced and you are moving at a constant speed. |

Why would you stay the same speed in a moving car? | because the forces on you are balanced. |

Describe a force. | A force is push, pull or twist. |

What force keeps us on the earth? | Answer: Gravity |

How would you measure a force? | Answer: With Newtons |

How do you work out Moments | Answer: Mass x distance to pivot |

Explain the difference between mass and weight | Weight is the force that pulls you down; mass is the Number of atoms in the body |

What will be different on the moon than on the earth: mass or weight? | Answer: The weight |

In a tug of war, when one team is pulling with a force of 100 N to the leftand the other 80 N to the right, what is the net force? | Answer: 20N to the left |

What is the force that keeps you afloat in water? | Answer: Upthrust |

Which of these will help a car go faster? | Answer: Streamlining |

What is the equation to work out the pressure? | force divided by area |

What is the equation to work out the area? | force divided by pressure |

What is the equation to work out the force? | pressure times the area |

What unit measures force? | newtons |

What is the equation to work out the distance? | speed times the time |

What is the equation to work out the time? | distance divided by speed |

What is the equation to work out the speed? | distance divided by time |

What is the effect of unbalanced forces on a moving object? | direction may change, or the object may slow down, or it may accelerate(go faster) |

What is a force ? | a force is a push or pull movement |

Name three types of forces? | gravity, up thrust and air resistance |

Is gravity a push or pull force? | pull |

Is up thrust a push or pull force? | push |

Is air resistance a push or pull force? | push |

Which force pulls you down when sky-diving? | gravity |

Which force slows you down while sky-diving? | air resistance |

Where does upthrust occur? | in water |

When you drive in a car which force hits against a car? | air resistance |

Which force keeps us on the ground so we don’t float away? | gravity. |

Forces can make things change shape, speed or direction true or false | True |

This person is pushing down on the chair with force of 650N. What other force is acting to make it balanced | Reaction of the floor |

In which direction does gravitational force apply | downwards |

Suggest what would happen to the weight of an astronaut who travelled to space | the weight will be the different because only the mass does not change but when you’re in space your weight changes it becomes lighter. |

What happens to air resistance as you move faster | ’ air resistance increases as there are more particles to hit you |

Why do dolphins have a streamlined shape | it enable them to move through water with the least possible water resistance. |

What happens to the air resistance when the parachute is opened | when the parachute opens the air resistance will become much greater which slows the person riding it |

What happens after the parachute is open for few seconds | As his speed reduces the air resistance will become less and eventually the forces will be the same again. |

When sheley Rudman won her gold medal in the bobsleigh skeleton suggest one thing she have done to make sure she went fast as possible | by making smaller surface area |

what is air resistance? | air resistance is the opposite force to movement and air resistance is created by particles! |

Explain why air resistance increases when you move faster? | more particles |

what does weight mean? | pull of gravity |

list 2 common units you can measure speed? | mph,km |

fill in the blank | |

if the forces on an object are balanced and the object is .............it will remain stationary | answer is stationary |

name contact forces | friction, upthrust, air resistance |

name non contact forces | gravity, magnetic field |

what is friction? | friction is a force that slows you down, created when one object rubs against another! |

What type of line of a distance graph shows that the moving object has stopped? | A straight horizontal line |

What is a stationary object? | An object that isn’t moving |

Complete the sentence “The smaller the surface area, the more ...” | Pressure |

Air Resistance is created out of ... | Particles hitting the moving object |

How do you work out the moment? | mass x distance |

Which of either the moon or the earth has more gravity? | The Earth |

True or false; Your body would float in water? | True |

How do you work our pressure? | force over area |

How do you work out the area? | Force over pressure |

How do you work out the force? | pressure times area |

Complete the sentence “Air resistance ... the car down.” | slows |

Complete the sentence “The more ... the more pressure” | force |

Define up thrust | up thrust is the upward force that liquid or gas use on a body floating in it. |

Define gravity | is the force that attracts a body towards the centre of the earth |

When are forces balanced? | Forces are balanced when they are equal in SIZE but opposite in direction: the forces cancel each other out. |

When are forces unbalanced? | Forces are unbalanced when one has a bigger force than the other |

What would an accelerating object look like on a speed time graph? | Sloping upwards. |

Which direction does air resistance go? | Opposite to the movement. |

How will a see-saw balance? | When the distance x weight on both sides is the same. |

On the can experiment, why did the can collapse? | Because of there was more pressure on the outside of the can than there was pressure inside the can |

On a distance vs time graph, what does a straight line mean? | The object is going at the same speed |

On a distance vs time graph, what does a flat line mean? | The object is not moving |

What does BLAST stand for? | Best fit Label Axis Scale Title |

If a slope on a line graph is steeper in the second part of a journey, what does it mean? | The object is moving faster in the second part of the journey |

If the force on a submarine porthole at a depth of 10m is 5000n, and the area of the porthole is 100m squared. What is the pressure? | pressure=force/area= 5000N divided 100m squared =50N/m squared |

Explain why have camels big feet? | so they don’t sink into soft sand because they have a large area so the pressure is large. |

If a box weighs 100N. it exerts a pressure of 25 N/m2 on a table. What is the area of the box in contact with the table | area=force/pressure=4m2 |