The speed of sound in water is 1,500 m/s. What is the wavelength of a sound wave with a frequency of 15,000 Hz in water?
a. 0.1 m
b. 1.0 m
C. 10 m
d. 100 m

What is the function of the commutator in a dc motor? a. to spin the magnet b. to change direct current into alternating current c. to change alternating current into direct current d. to spin the wire coil

Acup of coffee sits on the dashboard of an automobile. the car goes around a sharp curve. even though you hold the cup still, coffee still splashes out. this can best be explained due to a) density. b) friction. c) gravity. d) inertia.

What do elements in a family tend to share. a.) similar periods b.) similar groups c.) similar atomic symbols d.) similar chemical properties and characteristics