1. A particle is moving along the x-axis. Its position as a function of time is given as x = bt − ct 2 . a) What must be the units of the constants b and c, if x is in meters and t in seconds?

Why is alternating current more effective at long–distance travel than direct current? a. the power lines are made out of conductors. b. transformers increase or decrease voltage as needed. c. the ac generator is more efficient. d. ac has lower voltage than dc.

Select for each of the following statements whether it is correct or incorrect. (a) in an isothermal expansion of an ideal gas. (b) the temperature remains constant. (b) the pressure remains constant. (c) there is work done by the gas. (d) there is heat added to the gas. (e) the change in internal energy equals zero.

Smallest intensity of a stimulus that you can detect 50 percent of the time is