Why does a siren have a higher pitch as it approaches you?

The amplitude of the sound wave is increased.

The crests of the sound wave are spaced closer together.

The troughs of the sound wave are farther apart.

The period of the sound wave is increased.

Aperson walks first at a constant speed of 4.89 m/s along a straight line from point a to point b and then back along the line from b to a at a constant speed of 2.95 m/s. what is the average speed over the entire trip?

1. explain how you calculate the net force in any direction on the box. 2. suppose an upward force of 15n is added to the box. what will be the net vertical force on the box? 3. what force could be applied to the box to make the net force in the horizontal direction zero? explain. 4. suppose a force of 25n to the right is added to the box. what will be the net force to the right?

How is the ideal mechanical advantage of a wheel and axle calculated?