SAT Subject Physics Practice Question 474: Answer and Explanation
5. A rescue plane flying at 162 km/hr drops a survival package to a group of stranded skiers from a height of 70 m. After dropping the package the pilot of the plane continues to fly in a straight line. When the package strikes the ground it is
A. 85 m behind the plane.
B. 170 m behind the plane.
C. 255 m behind the plane.
D. 462 m behind the plane.
E. directly beneath the plane.
Correct Answer: E
The correct answer is (E). This is a curvilinear problem. The package already has the x-axis (horizontal) velocity of the plane. Even though the package accelerates toward the ground, its horizontal velocity remains exactly the same as when it left the plane, and that keeps the package moving along under the airplane until it strikes the ground.