A 60-kg woman stands on the very end of a uniform board, which is supported one-quarter of the way from one end and is balanced. What is the mass of the board?

a. 60 kg

b. 30 kg

c. 20 kg

d. 15 kg

e. 120 kg

What do waves transfer from place to place? a) motion b) energy c) matter d) water

If a hydrogen atom has one proton, two neutrons, and no electrons is this atom neutrally charged

If the distance between two masses is tripled, the gravitational force between them changes by a factor of

The terminals of a battery are connected across two resistors in series. The resistances of the resistors are not the same. Which of the following statements are correct? a. The potential difference across each resistor is the same. b.

Do different volumes of water have the same density? Why or why not?

Why doesn't a transformer work with direct current? why is ac required?

Which term describes the region in which an electron is most likely to be found? path cloud isotope orbital

The distance between two consecutive nodes of a standing wave is 21.9 cm. the hand generating the pulses moves up and down through a complete cycle 2.13 times every 3.65 s. find the velocity of the wave. answer in units of m/s.

Which statement is NOT true? Light travels with or without a medium Light travels faster than sound Sound must have a medium to travel through Both light and sound must have a medium to travel through

When light bends as it enters a different medium the process is known as what?