8. A box has a mass of 3 kg. The box is lifted from the floor and placed on 10 points a shelf. If the box gains a Potential Energy of 100 J, then how high is the
shelf? *
3.40 m
1.20 m
2.34 m
1.50 m

A6,600 kg train car moving at +2.0 m/s bumps into and locks together with one of mass 5,400kg moving at -3.0m/s. what is their final velocity? +0.50 m/s -1.0 m/s +2.5 m/s -0.25 m/s

The magnitude of the magnetic field at a certain distance from a long, straight conductor is represented by b. what is the magnitude of the magnetic field at twice the distance from the conductor? a. at twice the distance, the magnitude of the field is 4b.b. at twice the distance, the magnitude of the field is 2b.c. at twice the distance, the magnitude of the field is b/2.d. at twice the distance, the magnitude of the field is b/4.e. at twice the distance, the magnitude of the field remains equal to b.

What is the name of the perceived change in a sound wave’s frequency due to motion between the observer and the sound source?