Final answer:
It is true that C language does not check array boundaries when accessing an element, potentially leading to undefined behavior. The observed frequency does not become infinite when a source moves at the speed of sound, contrary to what might be implied by the Doppler effect. In a circuit diagram, it is false that the voltage is the same at every point since voltage can vary across components.
Step-by-step explanation:
When accessing an array element, the statement that the C language does not check whether the index is within the boundary of an array is true. C does not perform any bounds checking for array access, which means if an index is out of bounds, it could lead to undefined behavior, including accessing random memory locations, possible data corruption, and program crashes. In C, it is the programmer’s responsibility to ensure that the index is within the valid range of the array.
The observed frequency becomes infinite when the source is moving at the speed of sound is false. According to the Doppler effect, the observed frequency increases as the source approaches the observer, but it would not become infinite even if the source moves at the speed of sound.
In a circuit diagram, the statement that we can assume the voltage is the same at every point in a given wire is false. Voltage can differ across different points in a circuit depending on the presence of components and their arrangement. This is illustrated by the concept of voltage drop across components like resistors.