问题 选择题

下列有关行星运动的说法中,正确的是(   )

A.由ω=知,行星轨道半径越大,角速度越小

B.由a=rω2知,行星轨道半径越大,行星的加速度越大

C.由a=知,行星轨道半径越大,行星的加速度越小

D.由=m知,行星的轨道半径越大,线速度越小

答案

答案:D

ω=、a=rω2、a=,三式是匀速圆周运动各物理量之间的关系式,并不是行星运动的规律,行星运动的规律有开普勒第一、二、三定律(如r3/T2=k),动力学方程GMm/r2=mv2/r=mrω2,所以答案是D.

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DONALD SLOAN
Gates Hall
University of Kansas
Lawrence, KS 66045
913-243-1682
After May 2009:
46 Clayton Drive
St. Louis, MO 63130
314-726-8840
Objective
To work with the client(委托人)population in a social service position.
Education
B.A., University of Kansas, Lawrence, KS, 2009
Major: Social Services
Minor: Applied Psychology
Experience
Assistant Activities Supervisor, Fairview Nursing Home, Lawrence, KS, November 2006-present. Help organize and implement recreational activities for nursing home residents. Activities include crafts, dances, day trips, sing-alongs, and visiting performers.
Hotline Volunteer, Teen Crisis Center, Lawrence, KS, September 2006- May 2007. Handled crisis calls from teenagers in the community. Dealt with drug use, unwanted pregnancies, failing grades, and the breakdown of parent-teen relationships.
Nurse’s Aide, Danyers General Hospital, St. Louis, MO, Summer 2006. Assisted nurses in patient care. Took histories, updated charts, and helped prepare patients for surgery. 
Activities
University Concert Board. Work with other board members to plan and implement on-campus concerts.
Senior Gift Campaign. Help manage the campaign to raise funds for the senior class gift to the university.
Residence Hall Programming Board. Planned social events for Eggar Residence Hall.
Skills
Fluent in French. Water safety instructor. Skilled at working with people.
Interests
Skiing, softball, classical music, and guitar.
小题1:This passage is most probably ______.
A.an advertisement for enrolling new employees
B.a school report at the end of an academic year
C.a self-introduction meant to apply for a job
D.a part of a recommendation letter from a university
小题2:According to the “Experience” section, we can infer that Donald Sloan can be ____.
A.a wise leaderB.a skillful performer
C.a gifted scientistD.a good social worker
小题3:From the passage we can learn that Donald Sloan ______.
A.is good at singing and dancingB.is about to graduate from a university
C.has an interest in being a surgeonD.specializes in psychology