Grade 7 Science
Investigate forces, energy, and how the physical world works.
Unit Outline
Physics — Forces, Motion & Pressure
We are learning about types of forces, balanced and unbalanced forces, friction and drag, calculating speed, and understanding pressure.
Your Learning Journey
Assessment Criteria
All MYP Science assessments are marked against four criteria (A–D), each scored 1–8. Here is what each level looks like.
Knowing and Understanding
Explain scientific knowledge and apply it to solve problems.
Recalls some scientific knowledge with limited understanding.
Applies scientific knowledge to solve straightforward problems.
Applies scientific knowledge accurately and analyses information.
Applies scientific knowledge with precision, analysing and evaluating in unfamiliar contexts.
Inquiring and Designing
Design scientific investigations including variables, method, and safety.
States a basic problem or question. Identifies some variables.
Outlines a testable hypothesis. Designs a method with some detail.
Formulates a clear hypothesis. Designs a logical, detailed, safe method.
Formulates a precise, justified hypothesis. Designs a highly detailed, replicable investigation.
Processing and Evaluating
Collect, process, and interpret data. Evaluate the method and results.
Collects some data. Makes basic observations.
Processes data into tables/graphs. Identifies basic patterns.
Processes data accurately. Interprets trends and evaluates the method.
Processes data precisely. Draws justified conclusions and critically evaluates reliability.
Reflecting on the Impacts of Science
Discuss the implications of science on people and the environment.
States a basic connection between science and society.
Describes how science is applied and discusses an implication.
Explains the connections between science, society, and ethics with examples.
Critically evaluates the implications of science, considering multiple perspectives and ethical issues.
Lesson Slides
Worksheets
Review Games
Videos
Key Vocabulary
Essential terms for this unit. Use these to build your scientific vocabulary.
Forces
A push or pull that can change an object's speed, direction, or shape. Measured in Newtons (N).
A force of attraction between any objects with mass. Pulls everything towards Earth's centre.
A force opposing motion between two surfaces. Converts kinetic energy to heat.
Friction between an object and the air. Increases with speed and surface area.
Equal forces in opposite directions. Resultant force = 0. Object stays still or at constant speed.
Forces not equal. There is a resultant force causing acceleration or deceleration.
The overall force when all forces are combined. Determines the object's motion.
Motion & Pressure
How fast something moves. Speed = distance ÷ time. Units: m/s or km/h.
Force spread over an area. P = F ÷ A. Units: Pascals (Pa) or N/m².
The amount of matter in an object. Measured in kg. Does NOT change with location.
The force of gravity on an object. W = m × g. Measured in Newtons. Changes with gravity.
A device (spring balance) used to measure forces in Newtons.
🚀 Extension Activities
Go beyond the textbook. Choose an activity that interests you and challenge yourself.
Balloon Rocket Grand Prix
Design & TestBuild a balloon-powered car using recycled materials. Test it on a smooth floor. Measure distance travelled. Then modify ONE variable (wheel size, body weight, balloon size) and test again. Which modification improved performance most? Use Newton's Laws to explain why.
Bridge Building Challenge
Engineering DesignUsing only newspaper and tape, build a bridge between two desks that can hold the most weight. Test with textbooks. Calculate the forces involved. Why do some designs hold more than others? Research how the Nanjing Yangtze River Bridge was designed.
Parachute Design Investigation
Fair TestDesign and test parachutes of different sizes and materials. Drop from the same height and time the fall. Calculate average speed. Which design gives the lowest terminal velocity? Present your results as a scientific report.
Maglev Model
Research & BuildResearch how Shanghai's maglev train uses magnetic levitation. Can you build a simple model using magnets that demonstrates the principle? Document your design process and explain the forces involved.
Explore
Interactive simulations and tools. Use these to deepen your understanding.
Physics Calculator
Mr ZocchiCalculate F=ma, speed, pressure, and weight on different planets.
Forces & Motion Sim
PhETPush objects, add friction, explore Newton's Laws with real-time force arrows.
Forces & Motion
PhET SimulationApply forces to objects and see how they accelerate. Explore balanced and unbalanced forces.
Pressure Simulator
PhET SimulationExplore how pressure changes with depth and fluid type.
Forces Lab
Mr ZocchiAdd forces in any direction and see the resultant. Test scenarios: ssireum wrestling, rocket launch, maglev train.
Self-Quiz
Click a question to reveal the answer.
What is a force?
A push or pull that can change an object's speed, direction, or shape. Measured in Newtons (N).
Name three types of force.
Gravity, friction, air resistance, tension, normal (contact/reaction), magnetic, electrostatic.
What happens when forces are balanced?
Resultant force = 0. The object stays still or continues at constant speed (Newton's 1st Law).
A car has 5000N driving force and 3000N friction. What is the resultant force?
5000 − 3000 = 2000N forward. The car accelerates.
Speed = distance ÷ time. A cyclist travels 30 km in 1.5 hours. Find the speed.
30 ÷ 1.5 = 20 km/h.
What is pressure?
Force per unit area. P = F ÷ A. Units: Pascals (Pa).
A 900N force on 3m² area. What is the pressure?
P = 900 ÷ 3 = 300 Pa.
Why do sharp knives cut more easily?
Smaller area → higher pressure for the same force. P = F/A: less area = more pressure.
What is the difference between mass and weight?
Mass = amount of matter (kg), constant everywhere. Weight = force of gravity (N), changes with gravitational field strength.
Calculate weight: mass 60 kg, g = 10 N/kg.
W = mg = 60 × 10 = 600 N.
Common mistake: 'A moving object with no forces on it will slow down.' Why is this wrong?
Newton's 1st Law: an object in motion stays in motion unless acted on by a force. With no forces, it moves at constant speed forever.
Why does a falling skydiver eventually reach terminal velocity?
Air resistance increases with speed until it equals weight. Forces become balanced → constant speed (no acceleration).