1.4 Reference Frames and Relative Motion

• Objects in a non-inertial reference frame appear to experience fictitious forces like centrifugal force.


  True
• What is the formula for velocity?

  $v =$$\frac{\Delta x}{\Delta t}$
• What is the Galilean transformation equation for position?

  $r' =$$r - vt$
• A reference frame is a coordinate system used to describe the motion of an object.
• In an inertial reference frame, objects at rest or moving at constant velocity experience no net force.
• What is the formula for displacement?

  $\Delta x =$$x_{f} - x_{i}$
• What is the purpose of the Galilean transformation?

  To switch between inertial frames
• What is a reference frame used for in physics?

  Describing object motion
• Give an example of an inertial reference frame.

  Train moving at constant speed
• Match the quantity with its formula:

  Displacement ↔️ $\Delta x =$$x_{f} - x_{i}$

  Velocity ↔️ $v =$$\frac{\Delta x}{\Delta t}$

  Acceleration ↔️ $a =$$\frac{\Delta v}{\Delta t}$
• The Galilean transformation applies to two inertial reference frames moving relative to each other.

  True
• What is the key difference between inertial and non-inertial reference frames?

  Inertial frames are not accelerating
• Fictitious forces are real forces in non-inertial reference frames.

  False
• Velocity is defined as the rate of change of an object's position over time.
• In relative motion problems, the formula to convert velocities between reference frames is v' = v - u.
• An inertial reference frame is one that is not accelerating
• In non-inertial frames, Newton's laws do not directly apply without accounting for fictitious forces
• The Galilean transformation ensures kinematic quantities are consistent regardless of the observer's reference frame.
• Relative motion describes how an object's motion appears from different reference frames.


  True
• Examples of inertial reference frames include a stationary room or a train moving at a constant speed.
• Match the Galilean transformation equation with its corresponding quantity:

  Position transformation ↔️ r' = r - vt

  Velocity transformation ↔️ v' = v - u
• If a person walks east at 2 m/s inside a train moving east at 50 m/s, their velocity relative to the ground is 52 m/s.

  True