The Sun has a mass of 2.0 × 10^30 kg - Edexcel - GCSE Physics - Question 10 - 2020 - Paper 1
Question 10
The Sun has a mass of 2.0 × 10^30 kg.
A white dwarf has a mass of 3.4 × 10^29 kg.
Calculate the value of
mass of this white dwarf
mass of the Sun
Figure 18 is a dia... show full transcript
Worked Solution & Example Answer:The Sun has a mass of 2.0 × 10^30 kg - Edexcel - GCSE Physics - Question 10 - 2020 - Paper 1
Step 1
Calculate the value of mass of this white dwarf mass of the Sun
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To find the ratio of the mass of the white dwarf to the mass of the Sun, use the formula:
Value=mass of Sunmass of white dwarf
Substituting the given values:
Value=2.0×1030 kg3.4×1029 kg
Evaluating this gives:
Value=0.17
Step 2
Estimate the temperature of the Sun.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
From the graph provided (Figure 18), the estimated temperature of the Sun can be read off as approximately 5778 K.
Step 3
State how the brightness of a main sequence star changes with its temperature.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The general relationship is that the higher the brightness, the greater the temperature of the star. Higher temperature leads to increased energy output, resulting in greater luminosity.
Step 4
State how the brightness of a main sequence star changes with its mass.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The greater the mass, the higher the brightness of a main sequence star. More massive stars burn more brightly due to their higher gravitational pressure and temperature.
Step 5
Describe what happens during nuclear fusion.
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
During nuclear fusion, smaller nuclei (such as hydrogen) come together to form a larger nucleus (such as helium). This process occurs under extreme temperatures and pressures, overcoming the repulsion between the positively charged nuclei. As a result, energy is released, providing the necessary power for the star.
Step 6
Explain how a nebula may evolve into a main sequence star.
97%
121 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
A nebula, which is a cloud of gas and dust, can evolve into a main sequence star through several steps:
The gas and dust particles are pulled together due to gravitational attraction.
As they come closer, the density of the material increases, and its temperature rises due to gravitational heating.
Eventually, when the temperature is high enough for nuclear fusion to occur, a main sequence star is formed.
