Quiz 3 Flashcards
In the late 1800s, Kelvin and Helmholtz suggested that the sun stayed hot thanks to gravitational contraction. What was the major drawback of this idea
It predicted that the sun could last only about 25 million years, which is far less than the age of earth
What do we mean when we say that the sun is in gravitational equilibrium
There is a balance within the sun between the outward push of pressure and the inward pull of gravity
What is the approximate composition of the sun
70% Hydrogen, 28% helium, 2% other elements
What are the appropriate units for the suns luminosity
Watts
What is the average temp of the surface of the sun
6,000 kelvin
Which is closest to the temperature of the core of the sun
10 million Kelvin
From the center outward, which of the following lists the layers of the sun in the correct order
CRC PCC
Core, radiation zone, convection zone, photosphere, chromosphere, corona
Which layer of the sun do we normally see
Photosphere
The one you take pictures of
The core of the sun is
Hotter and denser than the surface
Why do sunspots appear dark in pictures of the sun
They actually are fairly bright but appears dark against even brighter background of the surrounding sun
How does the sun generate energy today?
Nuclear fusion
At the center of the sun, fusion converts hydrogen into
Helium, energy, and nutrinos
Suppose you put two protons near each other, because of the electromagnetic force the two protons will
Repel each other
The first step in the proton proton chain produces an anti electron or positron. What happens to the positron
It is rapidly converted to energy when it meets an ordinary electron resulting in matter antimatter annihilation
The overall fusion reaction by which the sun currently produces energy is
4h=1 He+energy
Which statements best describes the solar neutrino problem
Solar neutrinos have been detected, but in fewer numbers than predicted by theoretical models
Why are neutrinos so difficult to detect
Because they rarely interact with matter
What is possible solution to the solar neutrino problem
The electron neutrinos created in the sun change into another type of neutrino that we do not detect
What happens to energy in the convection zone of the sun
Energy is transported outward by the rising of hot plasma and the sinking of cooler plasma
Most of the energy produced in the sun is released in the form of visible light from the photosphere. However some energy is released from the upper layers of the solar atmosphere. Which of the following best describes where other form of light are released?
The chromosphere is the source of ultraviolet light, and the corona is the source of X rays
What is the granulation of the sun
The bubbling pattern in the photosphere produced by he underlying convection
What processes are involved in the sunspot cycle
The winding of magnetic field lines due to differential rotation
What observations characterize solar maximum
We see many sunspots on the surface of the sun
