Scientific Method
What is the first step of a scientific investigation?
Identify the question/problem or aim.
What is renewable energy?
Energy from a source that is naturally replenished/replaced. It is replaced within a human lifespan.
Name one type of force
Push, pull, gravitational force, friction, air resistance, magnetic force, tension, etc.
What simple machine is a ramp?
Inclined plane
Which of these is a renewable resource?
A. Coal
B. Oil
C. Sunlight
D. Natural gas
Sunlight
What is a hypothesis?
A prediction about what you think will happen in an investigation / an educated guess.
Name one renewable energy source.
Solar, wind, hydroelectric, geothermal or biomass.
Is gravity a contact or non-contact force?
Non-contact
Name three simple machines.
Any three: lever, inclined plane, wedge, pulley, screw, wheel and axle.
Is coal renewable or non-renewable?
Non-renewable.
In an experiment testing whether the amount of sunlight affects plant growth, what is the independent variable?
The amount of sunlight.
Which renewable energy source uses moving air to generate electricity?
Wind energy.
Name two contact forces.
Friction, air resistance, tension, applied force, normal force, etc.
Which simple machine is used to split or cut materials, such as a knife or axe?
Wedge
Explain why fossil fuels are considered non-renewable resources.
Fossil fuels take millions of years to form, so they are used much faster than they can be replaced naturally.
In an experiment, a student changes the amount of water given to plants and measures their height after two weeks. What is the dependent variable?
The height/growth of the plants.
Give one advantage and one disadvantage of using solar energy.
Advantage: Renewable and produces little/no greenhouse gases during operation.
Disadvantage: Depends on sunlight/weather and can be expensive to install.
A book is sitting still on a table. Gravity pulls it down while the table pushes it up. Are these forces balanced or unbalanced? Explain.
Balanced, because the forces are equal and opposite, so the book's motion does not change.
What simple machine is found in a pair of scissors, and why can scissors be considered a compound machine?
Levers; scissors contain two levers working together, along with wedges formed by the blades.
What is mine rehabilitation, and why is it important after mining has finished?
Mine rehabilitation is the process of repairing and restoring land after mining. It can involve reshaping the land, replacing soil and replanting vegetation to help restore the environment.
A student tests three different surfaces to see which allows a toy car to travel the furthest. They use the same car, release it from the same height and measure the distance travelled. Identify the independent variable, dependent variable and one controlled variable.
A town wants to reduce its reliance on fossil fuels. It has strong winds, lots of sunlight and a river running through it. Which two renewable energy sources could the town use, and why might they be suitable?
Any two suitable sources with reasonable explanations e.g. wind because of strong winds and hydroelectric because of the flowing river.
A 10 kg box is pushed to the right with a force of 50 N. Friction acts to the left with a force of 20 N. Are the forces balanced or unbalanced? What is the net force and direction?
Unbalanced. Net force = 30 N to the right.
A worker needs to move a heavy box into the back of a truck. They could lift it straight up or push it up a ramp. Which option requires less force, and which simple machine is being used?
Pushing it up the ramp requires less force. The ramp is an inclined plane.
A mining company has finished removing coal from a mine. Explain two ways the company could rehabilitate the site and why rehabilitation is important for the environment.
They could replace soil, reshape the land, plant native vegetation, restore waterways or create habitats for animals. Rehabilitation helps restore damaged ecosystems, encourage biodiversity and allows plants and animals to return to the area.