According to Newton, is a freely falling elevator an accurate inertial reference frame?
A. No, such a frame is accelerating toward the earth.
B. It is not a real inertial frame, but we can treat it as one if we ignore external gravitational forces acting on objects inside the frame.
C. Yes.
D. It depends (explain).
B. It is not a real inertial frame, but we can treat it as one if we ignore external gravitational forces acting on objects inside the frame.
You might also like to view...
Adding a secondary concave lens of carefully chosen different glass to the primary lens on a refractor allows
A) chromatic aberration to be reduced. B) more light to be gathered. C) greater magnification. D) X-rays to be focused. E) effects of atmospheric turbulence to be reduced.
Which of the following is furthest from the Sun?
A) a comet in the Oort cloud B) Pluto C) an asteroid in the asteroid belt D) Neptune E) a comet in the Kuiper belt
A CD with a diameter of 12.0 cm starts from rest and with a constant angular acceleration of 1.00 
acquires an angular velocity of 5.00 rad/sec. The CD continues rotating at 5.00 rad/sec for 15.0 seconds and then slows to a stop in 12.0 second with a constant angular deceleration. What is the total acceleration of a point 4.00 cm from the center at the time 2.00 seconds from the start?
A. 0.450 
B. 0.314
C. 0.215
D. 0.165
E. 0.100
How many galaxies are needed to get a fair sample to determine what fraction are ellipticals?
A: 5-10. B: 35-45. C: 75-100. D: About 500. E: Over 1000.