What does a car's speedometer display?
AThe magnitude of the instantaneous velocity
BThe average velocity over the whole journey
CThe direction of the instantaneous velocity
DThe total distance covered since the start
Answer & Solution
Correct answer: A. The magnitude of the instantaneous velocity
1. A speedometer reads the value at one instant, not a value averaged over a trip.
2. It shows the magnitude of the instantaneous velocity but not its direction.
3. Police issue tickets on that instantaneous reading.
4. The total distance covered is shown by the odometer instead.
_Source: OpenStax College Physics (CC BY 4.0), Ch 2 "Kinematics", section 2.3 Time, Velocity, and Speed_
Related questions
Measuring time at all depends on the fact that:An airplane passenger moving 4 metres toward the rear of the plane has a displacement recoA cyclist rides 3 km west then turns and rides 2 km east. The magnitude of the displacemenA scalar such as temperature can be negative, and there the minus sign indicates:An object with negative acceleration whose acceleration points the same way as its motion Deceleration is best defined as acceleration that is:An acceleration of 8.33 metres per second squared due west means the velocity changes by:The SI unit of acceleration is metres per second per second because acceleration is: