【单选题】Consider an object on a rotating disk a distance r from its center, held in place on the disk by static friction. Which of the following statements is NOT true concerning this object?
A.
If the angular speed is constant, the object has a zero acceleration.
B.
The object has a tangential acceleration only if the disk has an angular acceleration.
C.
The object always has a centripetal acceleration except when the angular speed is zero.
D.
If the angular speed is constant, the speed of object is also constant.
【单选题】Analyze the following code: public class Test1 { public Object max(Object o1, Object o2) { if ((Comparable)o1.compareTo(o2) >= 0) { return o1; } else { return o2; } } }
A.
The program has a syntax error because Test1 does not have a main method.
B.
The program has a syntax error because o1 is an Object instance and it does not have the compareTo method.
C.
The program would compile if ((Comparable)o1.compareTo(o2) >= 0) is replaced by (((Comparable)o1).compareTo(o2) >= 0).