69.
(A)
(B)
(C)
(D)
(E)
70.(E)
71.
(A)
(B)
(C)
(D)
(E)
72.
(A)
(B)
(C)
(D)
(E)
73.
(A)
(B)(A)
(B)
(C)
(D)BC ONLY QUESTIONS 69–76
In Questions 69–72, the motion of a particle in a plane is given by the pair of
equations x = 2t and y = 4t − t 2.
The particle moves along
an ellipse
a circle
a hyperbola
a line
a parabola
The speed of the particle at any time t is2( |3 − t| )
The minimum speed of the particle is
2
2
0
1
4
The acceleration of the particle
depends on t
is always directed upward
is constant both in magnitude and in direction
never exceeds 1 in magnitude
is none of these
If a particle moves along a curve with constant speed, then
the magnitude of its acceleration must equal zero
the direction of acceleration must be constant