Does a car speedometer measure speed, velocity, or both? Explain. 2. When an object moves with constant velocity does its average velocity during any time interval differ from its instantaneous velocity at any instant? Explain.
The Correct Answer and Explanation is :
- Does a car speedometer measure speed, velocity, or both? Explain.
A car’s speedometer measures speed, not velocity. Speed is a scalar quantity, which means it only measures the magnitude of motion (how fast the car is going) without regard to direction. The speedometer shows the rate at which the car travels along the road but does not provide information about the direction of motion.
Velocity, on the other hand, is a vector quantity, meaning it includes both the magnitude (speed) and the direction of motion. While the car’s speedometer gives the speed, the direction of motion is not provided by the device itself. For instance, if a car is moving at 60 mph northward, the speedometer only indicates 60 mph, but the velocity would be expressed as “60 mph north.”
In short, the car’s speedometer measures speed because it gives the magnitude of motion, but it does not account for the directional component, which is essential for defining velocity.
- When an object moves with constant velocity, does its average velocity during any time interval differ from its instantaneous velocity at any instant? Explain.
When an object moves with constant velocity, its average velocity and instantaneous velocity are the same during any time interval. This happens because velocity, in this case, remains unchanged over time.
- Instantaneous velocity refers to the velocity of an object at a specific point in time. It includes both the magnitude and the direction of motion at that moment.
- Average velocity is the total displacement (change in position) divided by the total time taken over an interval.
If the object’s velocity is constant, its instantaneous velocity is the same at every instant. Thus, the displacement per unit time remains unchanged. The average velocity is calculated over the entire time interval, and since the velocity does not vary, the average velocity will be identical to the instantaneous velocity at any point during that interval.
Therefore, when an object moves with constant velocity, its instantaneous velocity is equal to its average velocity at any time during its motion.