Although the production of heat may be bad in some cases, describe another example where the production of heat is good.

True or false A temperature change and a change of state can both occur at the same time as a substance gains or loses energy.

Which of the following are true for E = mc2? a. developed by John Dalton b. implies that a small change in mass produces a great deal of energy c. mainly used for nuclear reactions d. shows the relationship between meters and energy

Suppose a well-designed optical instrument is composed of two converging lenses separated by 14 cm. The focal lengths of the lenses are 0.60 and 4.5 cm. Is the instrument a microscope or a telescope

Three carts of masses m1 = 4.00 kg, m2 = 10.0 kg, and m3 = 3.00 kg move on a frictionless, horizontal track with speeds of v1 = 5.00 m/s to the right, v2 = 3.00 m/s to the right, and v3 = 4.00 m/s to the left as shown.

A circuit has an AC voltage source in series with a 50 ohm resistor and a 113 mH inductor. The frequency is 100 cycles/sec, and the peak voltage is 140 volts. Find the average power dissipated by the resistor. Solve using imaginary numbers.

8. A gas is contained in a horizontal piston-cylinder apparatus at a pressure of 350 kPa and a volume of 0.02 m3. Determine the work done by the piston on the gas if the cylinder volume is increased to 0.15 m3 through heating.

A 75.0 kg person stands on a scale in an elevator. (a) What does the scale read (in N and in kg) when the elevator is at rest?

The hinge at A and cable BDC support beam ABC. Cable BDC passes over the pulley D that is pinned to the ceiling. (Assume that the + x-axis is to the right and the + y-axis is up along the page.

The "zone of avoidance" a) Accounts for the absence of any planet between the orbits of Mars and Jupiter Prevents collisions between planets in the Solar System.

Electric current is ...