Practice Final Exam B – PHYS2001 – Fall 2010
1. A projectile is launched over level ground at a launch angle of 70o with an initial velocity
vo. At some later time while the projectile is on its way to the peak in its trajectory, its
velocity vector makes an angle of 50o with respect to the horizontal. What is the
magnitude of the projectile’s horizontal velocity at that point?
A. 0 B. g C. vocos50o D. vosin50o E. vocos70o
2. A jetliner, traveling northward, is landing with a speed of 90 m/s. Once the jet touches
down, it has 950 m of runway in which to reduce its speed to 7.5 m/s. Compute the
average acceleration (magnitude and direction) of the plane during landing (take the
positive direction to be northward).
A. 7.15 m/s2 B. -4.23 m/s2 C. 30.5 m/s2 D. -4.08 m/s2 E. -0.04 m/s2
3. Two identical balls, one red and one blue, are thrown horizontally from the top of a tall
building at the same time. The initial speed of the red ball is twice the initial speed of the
blue one. Which of the following is true?
A. The red ball reaches the ground first.
B. The blue ball reaches the ground first.
C. Both balls reach the ground at the same time but hit with different speeds.
D. Both balls reach the ground at the same time and hit with the same speed.
E. Both balls travel the same horizontal distance.
4. A major-league pitcher can throw a baseball in excess of 45.0 m/s. If a ball is thrown
horizontally at this speed and acts like a projectile, how much will it drop by the time it
reaches the catcher who is 15.0 m away from the point of release?
A. 0.544 m B. 0.333 m C. 0.788 m D. 3.00 m E. 15.0 m
5. The highest barrier that a projectile can clear is 19.7 m, when the projectile is launched at
an angle of 15.0o above the horizontal. What is the projectile’s launch speed?
A. 9.8 m/s B. 84.9 m/s C. 31.1 m/s D. 75.9 m/s E. 25.0 m/s
