Two small objects are suspended from threads. When the objects are moved close together, they attract one another. Which of the following could produce this result?
a. One object is negatively charged and the other is uncharged. b. One object is positively charged and the other is uncharged. c. One object is positively charged and the other is negatively charge.
d. All of the above could result in such attraction.
D
You might also like to view...
The equation has been proposed by Hausen for the transition range (2300 < Re < 8000) as well as for higher Reynolds numbers. Compare the values of Nu predicated by Hausen’s equation for Re = 3000 and Re = 20,000 at D/L = 0.1 and 0.01 with those obtained from Gnielinski correlation. Assume the fluid is water at 15°C flowing through a pipe at 100°C.
GIVEN
• Water flowing through a pipe
• The Hausen correlation given above
• Water temperature = 15°C
• Pipe temperature = 100°C
FIND
• The Nusselt number using the Hausen correlation and appropriate equations and charts in the text for Re = 3000 and 20,000 and D/L = 0.1 and 0.01
ASSUMPTIONS
• Steady state
• Constant and uniform pipe temperature
SKETCH
PROPERTIES AND CONSTANTS
for water at 15°C
Absolute viscosity (?b) = 1136 × 10–6 (Ns)/m2
Prandtl number (Pr) = 8.1 At 100°C ?s = 277.5 × 10–6 (Ns)/m2
Prs= 1.75
A wheel rotating about a fixed axis has a constant angular acceleration of 4.0 rad/s2. In a 4.0-s interval the wheel turns through an angle of 80 radians. Assuming the wheel started from rest, how long had it been in motion at the start of the 4.0-s interval?
A. 2.5 s B. 4.0 s C. 3.5 s D. 3.0 s E. 4.5 s
An electron is released from rest at the negative plate of a parallel plate capacitor. If the distance between the plates is 5 mm and the potential difference across the plates is 5 V, with what velocity does the electron hit the positive plate? (me = 9.1 × 10?31 kg, qe = 1.6 × 10?19 C.)
What will be an ideal response?
An atom of "anti-hydrogen" would be made of
A) an anti-proton and a positron. B) a positron and an electron. C) a proton and a positron. D) a high-frequency photon and a low-frequency photon. E) an anti-proton and a muon.