How did de broglie change our ideas about the behavior of matter?

Where is the potential energy throughout the loading, cocking, and releasing of the trebuchet?

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

An owl dives toward the ground with a constant velocity of 4.40 m/s at 53.0° below the horizontal. the sun is directly overhead and casts a shadow of the owl directly below it. what is the speed (in m/s) of its shadow on level ground?