In wave tanks, students investigated how water waves are affected by barriers and the depth of the water. They made diagrams of their observations
Which diagram shows reflection of water waves in the wave tank?
Solid Barrier
Barrier with
One Opening
O A
Incoming
Waves
Incoming
Waves
Deep
Water
Shallow
Water
Barrier with
Two Openings
D.
B.
Incoming
Waves
Incoming
Waves

Abox that has self-contained cable clamps holds two light switches. a two-wire no. 12 cable with ground feeds the box, and a pair of two-wire no. 12 cables (four conductors) with ground wires leaves the box to feed the light fixtures. the second switch is fed by a no. 12 jumper wire from the first switch. which one of the following box combinations would furnish the minimum allowable volume? a. two 3-inch × 2-inch × 21⁄2-inch gangable device boxes b. two 3-inch × 2-inch × 11⁄2-inch gangable device boxes c. two 3-inch × 2-inch × 23⁄4-inch gangable device boxes d. two 3-inch × 2-inch × 21⁄4-inch gangable device boxes