A 10-pound sack of potatoes falls from an airplane. As the velocity of the falling sack increases, so does the air resistance on it. When the air resistance equals 10 pounds, the acceleration of the sack will be
A. zero.
B. 9.8 m/s.
C. 9.8 m/s2.
D. 100 ft/s2.
Answer: A
You might also like to view...
Why did these astronomers take so many different pictures of the same patch of sky?
A: To "top" a previous study by rival astronomers, who took slightly fewer images. B: Galaxies have brightnesses that vary over hours or days, and they needed to be sure to get roughly equal light from all of them. C: To average over many images and keep only the consistent object details, filtering out random single-exposure events like charged particles from the solar wind. D: Needed a separate image for every nanometer-increment wavelength from 350nm to 800nm, to compile the final full-color image. E: It's not NASA's fault that pulsar in the foreground kept blinking!
Radioactive dating methods and other dating methods indicate that hominids have been on Earth for about
A) 15 billion years. B) 5 billion years. C) 5 million years. D) 100,000 years. E) 5000 years.
These are found on the side of the Moon that faces Earth, but not on the far side
A) Highlands B) Maria C) Craters D) Mountains E) Valleys
A ringing alarm clock is placed in a bell jar, which is then sealed, and the air is pumped out of it. Which effect will most likely occur?
1.The sound of the ringing alarm clock will get louder as the air is pumped out. 2.The sound of the ringing alarm clock will get softer as the air is pumped out. 3.No noticeable change will occur as the air is pumped out. 4.The sound will diminish completely immediately after the air has begun to be pumped out.