SCI exam

Chapter 1: Scientific Method

• Steps of the Scientific Method:

  1. Ask a Question

  2. Do Background Research

  3. Form a Hypothesis

  4. Conduct an Experiment

  5. Analyze Data

  6. Draw a Conclusion

  7. Communicate Results

• Variables:

  • Independent Variable: The factor changed in an experiment.

  • Dependent Variable: The factor measured.

  • Control Variables: Factors kept constant.

• Hypothesis vs. Theory vs. Law:

  • Hypothesis: A testable prediction.

  • Theory: A well-tested explanation.

  • Law: A statement describing a natural phenomenon.

Chapter 2: Newton’s Laws of Motion

1st Law (Law of Inertia)

• An object in motion stays in motion, and an object at rest stays at rest unless acted upon by an external force.

2nd Law (F = ma)

• Force = Mass × Acceleration

• More force = More acceleration

• Units: Newtons (N)

3rd Law (Action-Reaction)

• For every action, there is an equal and opposite reaction.

Chapter 3: Energy and Heat

• Types of Energy:

  • Kinetic Energy (KE): Energy of motion → KE=12mv2KE = \frac{1}{2} mv^2KE=21​mv2

  • Potential Energy (PE): Stored energy → PE=mghPE = mghPE=mgh

• Forms of Energy:

  • Mechanical

  • Thermal

  • Chemical

  • Electrical

  • Nuclear

  • Radiant

• Heat Transfer:

  1. Conduction: Direct contact.

  2. Convection: Movement in fluids (liquids & gases).

  3. Radiation: Energy transfer through waves (sunlight).

Chapter 4: Laws of Thermodynamics

1st Law: Law of Energy Conservation

• Energy cannot be created or destroyed, only transferred or converted.

2nd Law: Entropy Increases

• Heat flows from hot to cold, and systems tend toward disorder.

3rd Law: Absolute Zero

• Absolute zero (0 K) is the lowest temperature where motion stops.

Chapter 5: Electricity

• Ohm’s Law:

  • Voltage (V) = Current (I) × Resistance (R)

  • Units:

    • Voltage = Volts (V)

    • Current = Amps (A)

    • Resistance = Ohms (Ω)

• Circuits:

  • Series Circuit: One path for current.

  • Parallel Circuit: Multiple paths for current.

• Electric Power:

  • P=VIP = VIP=VI (Power = Voltage × Current)

  • Measured in Watts (W).

  • Total Current: The total current in a parallel circuit is the sum of the currents through each path, which can be calculated as I_total = I_1 + I_2 + I_3 + ... + I_n.