Homework hint: All problems in the text have answers at the back of the book! Some problems require just a written response, while others ask you to calculate something. Please write up all answers clearly, completely, and as succinctly as possible. You can work with others, but your final answers must be written up on your own.
Question 3.
Go to the Solar System
Collisions program.
a) The Hellas impact basin on Mars is about 1800 km in diameter
and about 6 km deep. Use the Collision Calculator with v=20 km/s to
work out how large the impactor must have been if it was an asteroid
(made of rock) or a comet (made of ice).
b) Use the rocky and
icy impactors from part a) on the Earth and the Moon and compare the crater
diameters and depths to the ones on Mars. Can you guess at the reason
for the differences? Explain your answer.
Question 4. Once more, use the Solar System
Collisions program.
The energy contained in the motion of an
object of mass m moving at speed v is m*v^{2}/2. In this problem, you
will test how well this formula fits the energy released a high speed
impact with Earth.
a) Go back to the table that you created in
HW#1. How much does the impact energy increase for each factor of ten
increase in diameter? Is this consistent with the formula? Why or why
not?
b) Now run several simulations for a 1km object hitting Earth
at different velocities: 15, 30 and 60 km/s. Record the impact
energies and show how well they match the predictions of the
equation. Use ratios as you did in problem 1 of HW#2.