IB myp 4-5 physics – Practice Questions- All Topics
Topic :Astrophysics-The Solar System Planets and Satellites
Topic :Astrophysics– Weightage : 21 %
All Questions for Topic :Classifications of stellar bodies, stellar composition, astronomers, life cycle of a star
Question (6 marks)
Many years ago, people believed that all the planets and the Sun orbited Earth. This is known as the geocentric model. As viewed from Earth, Mars takes the path shown in the animation.
Question a (2 mark)
Suggest why this observation is not consistent with the geocentric model of the solar system.
▶️Answer/Explanation
Ans:
Mars seems to change the direction and if earth is considered to be at the center then mars would orbit in a circular path and therefore, this observation is not consistent with the geocentric model of the solar system.
Question b (2 mark)
When Earth and Mars are $6 \times 10^{10} \mathrm{~m}$ apart, a radio signal travelling at $3 \times 10^8 \mathrm{~ms}^{-1}$ will take $200 \mathrm{~s}$ to travel between the planets.
Calculate the time for the radio signal to travel from Earth to Mars when they are $4 \times 10^{11} \mathrm{~m}$ apart. Give your answer to the nearest minute.
▶️Answer/Explanation
Ans:
time for the radio signal $=\frac{\left(4 \times 10^{(11)}\right)}{3 \times 10^8}=1333.333333$
time for the radio signal in $\min =\frac{1333.33}{60}=22.22216667$
time for the radio signal in $\mathrm{min} = 22 \mathrm{~min}$
Question:
If the Earth were shrunk to the size of a football with a radius of 11cm, how high would Mount Everest be?
▶️Answer/Explanation
Ans: \(\frac{0.11}{6371000}\times 8848=1.5\times 10^{-4}m\)