The more precisely the position of a particle is known,
A. the more precisely its momentum can be known.
B. the more precisely its energy can be known.
C. the less precisely its momentum can be known.
D. the shorter its deBroglie wavelength is.
C. the less precisely its momentum can be known.
You might also like to view...
A thin-walled cylindrical tank with a diameter of 2.0 m and wall thickness of 18 mm is open at the top. The height h of water (weight density 5 9.81 kN/m3) in the tank at which the circumferential stress reaches 10 MPa in the tank wall is approximately:
(A) 14 m
(B) 18 m
(C) 20 m
(D) 24 m
A convex mirror has a focal length of ?20 cm. What is the object distance if the image distance is ?10 cm?
A. 10 cm B. 40 cm C. 60 cm D. 20 cm E. 30 cm
Air at 30°C enters a rectangular duct 1-m-long and 4 mm by 16 mm in cross-section at a rate of 0.0004 kg/s. If a uniform heat flux of 500 W/m2 is imposed on both of the long sides of the duct, calculate (a) the air outlet temperature (b) the average duct surface temperature, and (c) the pressure drop.
GIVEN
• Air flowing through a rectangular duct
• Inlet bulk air temperature (Tb,in) = 30°C
• Duct length (L) = 1 m
• Duct height (H) 4 mm = 0.004 m
• Duct width (w) = 16 mm = 0.016 m
• Air mass flow rate ( m ) = 0.0004 kg/s
• Uniform heat flux (q/A) = 500 W/m2 on the long sides
FIND
(a) Air outlet temperature (Tb,out)
(b) The average duct surface temperature (Ts)
(c) The pressure drop (? p)
ASSUMPTIONS
• The short sides of the duct are insulated
• Entrance effects are negligible
SKETCH
A boy kicks a football from ground level with an initial velocity of 20 m/s at an angle of 30° above the horizontal. How long does it take for the ball to rise to the highest point of its trajectory?
A) 1.0 s B) 1.8 s C) 2.0 s D) 3.5 s E) 0.5 s