Instructor: Dr. Tatiana Erukhimova Physics 218: Mechanics Instructor: Dr. Tatiana Erukhimova Lecture 10

A faulty model rocket moves in the xy-plane (the positive y-direction is vertically upward). The rocket’s acceleration has components ax(t)=t2 and ay(t)=-t, where =2.50 m/s4, =9.00 m/s2, and =1.40 m/s3. At t=0 the rocket is at the origin and has velocity with and Calculate the velocity and position vectors as functions of time. What is the maximum height reached by the rocket? What is the horizontal displacement of the rocket when it returns to y=0?

A physics professor did daredevil stunts in his spare time A physics professor did daredevil stunts in his spare time. His last stunt was an attempt to jump across a river on a motorcycle. The takeoff ramp was inclined at 53.00, the river was 40.0 m wide, and the far bank was 15.0 m lower than the top of the ramp. The river itself was 100 m below the ramp. You can ignore air resistance. a) What should his speed have been at the top of the ramp to have just made it to the edge of the far bank? b) If his speed was only half the value found in (a), where did he land?

First exam Tuesday, September 17, 7 – 8 pm Sections 549, 550 105 HELD Sections 551, 552 107 HELD Sections 570, 571 109 HELD

No calculators and cell phones BRING YOUR STUDENT ID! No calculators and cell phones All liquids, gels and aerosols must be in three-ounce or smaller containers.

What is included? Chapters 1-4 Kinematics, vectors

Kinematics

In components:

If is given, you can find and

Vectors

Friendly advice DO NOT…

DO NOT use Const acceleration case formulas when acceleration is a function of time. You have to integrate or differentiate! What are the Const acceleration case formulas?

DO NOT write the vector sign over a projection!

Do Not Forget to Write down what is given and express the answer in terms of what is given Box the answer Indicate the origin and positive x and y

Have a great day! Reading: Chapter 5