Q: Extract the answer to the question from the following context. Question: What is the ideal source of power? Context: A PM motor does not have a field winding on the stator frame, instead relying on PMs to provide the magnetic field against which the rotor field interacts to produce torque. Compensating windings in series with the armature may be used on large motors to improve commutation under load. Because this field is fixed, it cannot be adjusted for speed control. PM fields (stators) are convenient in miniature motors to eliminate the power consumption of the field winding. Most larger DC motors are of the "dynamo" type, which have stator windings. Historically, PMs could not be made to retain high flux if they were disassembled; field windings were more practical to obtain the needed amount of flux. However, large PMs are costly, as well as dangerous and difficult to assemble; this favors wound fields for large machines.
A: wound fields for large machines

Q: Extract the answer to the question from the following context. Question: Which of the following is not a continental rationalist: Descartes, John Locke or Leibniz? Context: Philosophical empiricists hold no knowledge to be properly inferred or deduced unless it is derived from one's sense-based experience. This view is commonly contrasted with rationalism, which states that knowledge may be derived from reason independently of the senses. For example, John Locke held that some knowledge (e.g. knowledge of God's existence) could be arrived at through intuition and reasoning alone. Similarly Robert Boyle, a prominent advocate of the experimental method, held that we have innate ideas. The main continental rationalists (Descartes, Spinoza, and Leibniz) were also advocates of the empirical "scientific method".
A: John Locke

Q: Extract the answer to the question from the following context. Question: Which of the following was not a candidate for the Republican presidential nomination: Eisenhower, Nixon, or Taft? Context: President Truman, symbolizing a broad-based desire for an Eisenhower candidacy for president, again in 1951 pressed him to run for the office as a Democrat. It was at this time that Eisenhower voiced his disagreements with the Democratic party and declared himself and his family to be Republicans. A "Draft Eisenhower" movement in the Republican Party persuaded him to declare his candidacy in the 1952 presidential election to counter the candidacy of non-interventionist Senator Robert A. Taft. The effort was a long struggle; Eisenhower had to be convinced that political circumstances had created a genuine duty for him to offer himself as a candidate, and that there was a mandate from the populace for him to be their President. Henry Cabot Lodge, who served as his campaign manager, and others succeeded in convincing him, and in June 1952 he resigned his command at NATO to campaign full-time. Eisenhower defeated Taft for the nomination, having won critical delegate votes from Texas. Eisenhower's campaign was noted for the simple but effective slogan, "I Like Ike". It was essential to his success that Eisenhower express opposition to Roosevelt's policy at Yalta and against Truman's policies in Korea and Chinamatters in which he had once participated. In defeating Taft for the nomination, it became necessary for Eisenhower to appease the right wing Old Guard of the Republican Party; his selection of Richard M. Nixon as the Vice-President on the ticket was designed in part for that purpose. Nixon also provided a strong anti-communist presence as well as some youth to counter Ike's more advanced age.
A: Nixon

Q: Extract the answer to the question from the following context. Question: The most heat-treatable alloys are decided but only? Context: Conversely, most heat-treatable alloys are precipitation hardening alloys, which produce the opposite effects that steel does. When heated to form a solution and then cooled quickly, these alloys become much softer than normal, during the diffusionless transformation, and then harden as they age. The solutes in these alloys will precipitate over time, forming intermetallic phases, which are difficult to discern from the base metal. Unlike steel, in which the solid solution separates to form different crystal phases, precipitation hardening alloys separate to form different phases within the same crystal. These intermetallic alloys appear homogeneous in crystal structure, but tend to behave heterogeneous, becoming hard and somewhat brittle.
A:
Conversely