least seven sentences explaining momentum conservation, comparing/contrasting it to energy conservation. You should discuss its basic definition, situations that are well-suited for it, the relevant formulae, and the general problem-solving process with momentum conservation.

2. The common theory for the extinction of the dinosaurs about 65 million years ago is that an asteroid called Chicxulub inelastically struck the Earth, depositing dust into the atmosphere and cooling the Earth by about 26 oC for 3 years. Assume this asteroid was roughly spherical, with a diameter of 2 km and mass of 10 teragrams, and that it struck the Earth with a speed of about 40,000 m/s. Choose a reference frame with the Earth at rest. (You may need to look up some information about teragrams and the Earth for this problem.)

a. Draw a diagram of the problem before and after the collision, labeling all relevant variables. Specify which objects are included in your system.

b. Explain an expression for the momentum of the Earth and the asteroid prior to the collision.

c. Explain an expression for the momentum of the combined mass after the collision.

d. Use conservation of momentum to find the recoil speed of the Earth after the collision. How does this

value compare with the orbital speed of the Earth around the Sun?