Choose the correct definition for a closed switch.
a. the current through it is zero.
b. the voltage across it can be any value depending on the circuit the current that varies either in magnitude or direction with time.
c. the voltage across it is zero. the current through it can be any value depending on the circuit.
d. the current is constant in magnitude and direction with respect to time.

Acylinder with a movable piston contains 11.7 moles of a monatomic ideal gas at a pressure of 1.32×10^5 pa. the gas is initially at a temperature of 300 k. an electric heater adds 43200 j of energy into the gas while the piston moves in such a way that the pressure remains constant. cp=20.79 j k^−1 mol^−1 for a monatomic ideal gas, and that the number of gas molecules is equal to avogadro's number (6.022×10^23) times the number of moles of the gas. (a) what is the temperature of the gas after the energy is added? (b) what is the change in volume of the gas? (c) how much work is done by the gas during this process?

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?

Consider two regions of space containing a static electric field, region a and region b. in region a the equipotential lines are more closely spaced than those in region b. what can be said about the relative strength of the electric field in the two regions? a) the electric field in region a is stronger th