physics paper2-forces reviewpt1

• What does the gradient of a distance-time graph represent?

  Speed
• An object can be traveling at constant speed while its velocity is changing.
• An object has negative acceleration when it is slowing down.
• How can you find the distance traveled from a velocity-time graph?

  Area under the graph
• A resultant force is the single force that replaces multiple forces acting on an object.
• What is the unit of force?

  Newton
• Distance is a scalar quantity.
• For an object moving at constant speed, the distance traveled can be calculated using the equation: distance = speed x time.
• Match the activity with a typical speed:

  Walking ↔️ 1.5 m/s

  Running ↔️ 3 m/s

  Cycling ↔️ 6 m/s
• Why does motion in a circle involve changing velocity even with constant speed?

  Direction is changing
• The speed of an object can be calculated from the gradient of its distance-time graph.
• Negative acceleration is also called deceleration.
• What is the unit of acceleration?

  m/s²
• The area under a velocity-time graph represents the distance traveled.
• Steps to analyze a velocity-time graph:

  1️⃣ Identify the axes and units

  2️⃣ Calculate the area under the graph

  3️⃣ Determine the gradient to find acceleration
• The equation for uniform acceleration is $v^{2} - u^{2} =$$2as$, where v is final velocity, u is initial velocity, a is acceleration, and s is displacement.
• What is Newton's first law of motion?

  Object remains at rest
• Inertia is the tendency of objects to resist changes in their state of motion.
• Newton's second law states that acceleration is proportional to force and inversely proportional to mass.
• What equation represents Newton's second law?

  F = ma
• Newton's third law states that forces between two interacting objects are equal and opposite.
• The Earth's gravitational field strength is approximately 9.8 N/kg, which means a 1 kg mass experiences a downward force of 9.8 N.
• What happens to the resultant force on a falling object as it reaches terminal velocity?

  Becomes zero
• An object with more mass has more momentum than an object with less mass moving at the same speed.
• What is conserved in a closed system according to the conservation of momentum?

  Total momentum