Ask a New Question
Menu

Marcel is performing the first test on his company's new electric car. During the test, the electric car reaches a maximum speed of 81 mph.

The performance test results of the electric car can be modeled by the following graph, where x represents time, in seconds at the start of the test, and y represents the speed, in miles per hour.

The graph shows a downward parabola vertex at (6, 80). The parabola starts from the origin, passes through (3, 60), (9, 60), and ends at (12, 0)

Which of the following statements is true about this situation?

A.
The electric car is not moving at 4 seconds and 8 seconds.
B.
The electric car is not moving at 0 seconds and 12 seconds.
C.
The electric car is not moving at 0 seconds and 6 seconds.
D.
The electric car is not moving at 6 seconds and 12 seconds.

1 answer

To analyze the situation described in the given test results, we need to interpret the information about the speed of the electric car over time.

  1. The graph is described as a downward parabola with its vertex at (6, 80), indicating that at 6 seconds the car reaches its maximum speed of 80 mph.
  2. The parabola starts at the origin (0, 0), which means that at 0 seconds, the car's speed is 0 mph (it is not moving).
  3. The parabola passes through the points (3, 60) and (9, 60), indicating that the car is moving at 60 mph at those times.
  4. It ends at (12, 0), indicating that at 12 seconds, the car's speed is again 0 mph (it is not moving).

Now, let's evaluate the options:

A. The electric car is not moving at 4 seconds and 8 seconds.

  • At 4 seconds, the car's speed is not mentioned specifically, and since the car reaches its max speed up to (6, 80) and is slowing down till (12, 0), 4 seconds will have some speed. At 8 seconds, the car would still be moving (as it is 60 mph at 9 seconds). Thus, this statement is false.

B. The electric car is not moving at 0 seconds and 12 seconds.

  • Both of these points are true; at 0 seconds, the speed is 0 mph, and at 12 seconds, the speed is also 0 mph. Thus, this statement is true.

C. The electric car is not moving at 0 seconds and 6 seconds.

  • The car is not moving at 0 seconds, but it is moving at 6 seconds (80 mph). Thus, this statement is false.

D. The electric car is not moving at 6 seconds and 12 seconds.

  • At 6 seconds, the car is moving at its maximum speed of 80 mph. Therefore, this statement is false.

Based on this analysis, the correct answer is:

B. The electric car is not moving at 0 seconds and 12 seconds.