<span>A student hears a police siren.
The arithmetic of the Doppler Effect shows that if the distance between
the source and observer is changing, then the observer hears a different
frequency compared to the frequency actually radiating from the source.
Thus the first four choices would cause the student to hear a different
frequency:
-- if the student walked toward the police car
-- if the student walked away from the police car
-- if the police car moved toward the student
-- if the police car moved away from the student
The last two choices wouldn't affect the frequency heard by the student,
since the perceived frequency of a sound doesn't depend on its intensity.
-- if the intensity of the siren increased
-- if the intensity of the siren decreased.</span>
0.029 m/s ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
Answer is B.
Because velocity is vector quantity, so magnitud and direction are needed to define it.
Since velocity means the speed(magnitude) of some object in a given direction, so it’s units are usually measured by meters/ seconds
The force required to push the box upward is 145.3N and the force to pus the box downward is -109.3N
Data given;
- mass = 15kg
- angle = 30 degree
- acceleration = 1.2 m/s^2
- acceleration due to gravity = 9.8 m/s^2
<h3>Force against gravity</h3>
To move the plane upward, the box will move against gravity.
Let's solve for F
<h3>Force towards gravity</h3>
When the force pushes the box down the inclined plane, it moves towards gravity.
The force required to push the box upward is 145.3N and the force required to push the box downward is -109.3N
Learn more on force across an inclined plane here;
brainly.com/question/11888124
