A student walks east 100 meters in 2 minutes. She then walks north 200 meters in 4 minutes. Which statement is true?(1 point)
Responses
Her velocity changes because her direction changes.
Her velocity changes because her direction changes.
Her velocity is constant because her speed is constant.
Her velocity is constant because her speed is constant.
Her velocity changes because her speed varies.
Her velocity changes because her speed varies.
Her velocity is constant because her direction is constant.
Her velocity changes because her direction changes.
The correct statement is: Her velocity changes because her direction changes.
To determine which statement is true, we need to understand the concepts of velocity, speed, and direction.
Velocity is a vector quantity that describes the rate at which an object changes its position. It includes both the speed and direction of the motion. Speed, on the other hand, is a scalar quantity that only describes the rate of motion without considering the direction.
In the given scenario, the student walks east for 100 meters in 2 minutes, and then north for 200 meters in 4 minutes. Since both distance and time are given for each segment of the motion, we can calculate the speed of each segment separately.
For the first segment (walking east), the speed can be calculated by dividing the distance (100 meters) by the time (2 minutes):
Speed = 100 meters / 2 minutes = 50 meters/minute
For the second segment (walking north), the speed can be calculated similarly:
Speed = 200 meters / 4 minutes = 50 meters/minute
As we can see, the speed is constant for both segments, and both speeds are equal at 50 meters/minute.
Now let's consider the direction. Initially, the student walks east, and then changes direction to walk north. Since the direction changes, it means the student's velocity also changes. Velocity takes into account both speed and direction, so if the direction changes, the velocity changes as well.
Therefore, the true statement is:
Her velocity changes because her direction changes.