Forces and Motion
What is a force?
A force is a push or pull on an object.
Name two types of energy resources used to move things.
Fossil fuels, wind, water, batteries.
Define speed and state its units.
Speed is how fast something is moving. Units: m/s or km/h.
What is a lever and how does it work?
A lever is a rigid bar that pivots around a point to move a load with less effort.
What is static electricity?
Static electricity is the build-up of electric charge on a surface.
Define top speed
Top speed is the highest speed an object can reach
Describe how energy is stored and transferred.
Energy can be stored in fuels, batteries, springs, and transferred as heat, light, sound, or movement.
What is the formula for speed?
Speed = Distance ÷ Time
How can the size of a force be increased?
By increasing the distance from the pivot or applying more force.
What happens when an object gains or loses electrons?
Gaining electrons = negative charge; Losing electrons = positive charge.
How can friction be reduced
By using smooth surfaces, lubricants like oil, or using wheels/rollers.
What is the definition of efficiency?
Efficiency = (Useful energy output / Total energy input) × 100%.
Rearrange the formula for distance and time.
Distance = Speed × Time.
Time = Distance ÷ Speed.
What is the formula for calculating turning forces?
Turning force (moment) = Force × Distance from pivot.
Explain what happens with same and opposite charges.
Opposite charges attract, same charges repel.
What is terminal velocity?
Terminal velocity is the constant speed reached when the force of gravity is balanced by air resistance.
What is the difference between renewable and non-renewable resources? Give examples.
Renewable resources can be replaced (e.g. wind, solar). Non-renewable cannot be replaced (e.g. coal, oil).
what is mean/average speed?
total distance travelled/total time taken
Why are levers useful in real-life applications?
They reduce the effort needed to move heavy objects by increasing force through distance.
What is a Van de Graaff generator used for?
It generates static electricity to demonstrate electric charge effects.
Name 5 different types of forces and describe what they do.
Gravity (pulls objects down), Friction (slows things down), Air resistance (slows objects moving through air), Magnetic force (attracts or repels magnetic materials), Upthrust (acts upwards in liquids).
What is nuclear fuel? Give examples and explain its use.
Nuclear fuel like uranium releases energy from atomic reactions and is used in power plants.
Explain what a distance-time graph shows when an object is at rest.
A flat horizontal line on a distance-time graph indicates no movement.
Define equilibrium and explain how it happens.
Equilibrium occurs when clockwise and anticlockwise moments are equal.
Explain how an insulating material can become charged by rubbing.
Rubbing transfers electrons, giving the material a static charge.