A fireman is sliding down a fire pole. As he speeds up, he tightens his grip on the pole, thus increasing the vertical frictional force that the pole exerts on the fireman. When the force on his hands equals his weight, what happens to the fireman?
A) The fireman comes to a stop.
B) The fireman descends with slower and slower speed.
C) The fireman descends with a smaller but non-zero acceleration.
D) The fireman continues to descend, but with constant speed.
E) The acceleration of the fireman is now upward.
D
You might also like to view...
The magnetic force on a point charge in a given magnetic field and at a given speed is largest when it
A. has velocity components both parallel to and perpendicular to the field. B. moves perpendicular to the magnetic field. C. moves in the direction opposite to the magnetic field. D. moves in the direction of the magnetic field.
From 1979 to 1999 Pluto was closer to the sun than
a. Earth. b. Uranus. c. Neptune. d. Saturn. e. Jupiter
The ____ of an object depends on the diameter of the object and the distance to the object
a. apparent brightness b. apparent magnitude c. zenith d. angular diameter e. color
The complexity of any life present in Europa's subsurface ocean is mainly limited by the
A) amount of water in the ocean B) amount of available energy to sustain it C) average temperature of the water D) amount of organic material present