The Fraunhofer lines in the solar spectrum are actually:
A) emission lines from hot gases in the chromosphere of the Sun.
B) emission sections of the continuous spectrum of the photosphere.
C) Zeeman lines around sunspots due to their strong magnetic fields.
D) absorption lines due to the thin outer layer above the photosphere.
E) redshifted lines due to the Sun's rotation.
D
You might also like to view...
Two wheels have the same total mass M and radius R. One wheel is a uniform disk. The other is like a bicycle wheel, with lightweight spokes connecting the rim to a small hub. Which likely has the larger moment of inertia?
A. The solid disk. B. The wheel with spokes. C. The moment of inertia will be nearly the same for both. D. We need more information to answer.
A 910-kg object is released from rest at an altitude of 1200 km above the north pole of the earth
If we ignore atmospheric friction, with what speed does the object strike the surface of the earth? (G = 6.67 × 10-11 N ? m2/kg2, Mearth = 5.97 × 1024 kg, the polar radius of the earth is 6357 km) A) 2.2 km/s B) 4.5 km/s C) 2.7 km/s D) 4.8 km/s E) 3.2 km/s
Which sequence of formation by age is correct, oldest to youngest?
A) Dark nebulae, planetary nebulae, emission nebulae B) Spiral arms, bulge, halo C) Halo, spiral arms, globular clusters D) Globular clusters, emission nebulae, open clusters
Two masses are connected by a string which passes over a pulley with negligible mass and friction. One mass hangs vertically and one mass slides on a frictionless 30.0 degrees incline. The vertically hanging mass is 6.00 kg and the mass on the incline is 4.00 kg. The acceleration of the 4.00 kg mass is
A. 2.98 
B. 3.92
C. 5.88
D. 6.86
E. 7.84