AP Physics Questions (topic: circular motion & gravitation)

Discus: SAT/ACT Tests and Test Preparation: October 2003 Archive: AP Physics Questions (topic: circular motion & gravitation)
 By Jason817 (Jason817) on Tuesday, October 21, 2003 - 07:04 pm: Edit

I need help doing these. Can you plz show houw you did them. Thanks a lot.

1. A car speeds around a curve banked at 33.0 degress at 23.0 m/s. Find the radius of the curvature assuming that no friction exists between the tires and the roadway.

2. Suppose the car (from #1) speeds up to 30.0 m/s. What is the minimum coefficient of friction required of the road/tires in order that the care safely negotiates the curve?

3. The following hypothetical solar system is made up of 3 masses. The star has a mass of 2.00x10^32 kg and is fixed in space. Planet 2 has a mass of 5.88x10^27 kg and is located 4.25 AU from the star. Assume that both planetary orbits are perfect circles and the planets are positioned as shown. Calculate the period of Planet 1 and Planet 2.

At the position [in the pic in my profile], find the net force on the star due to Planet 1 and Planet 2 (don't forget to include direction).

 By Supercool1 (Supercool1) on Tuesday, October 21, 2003 - 07:16 pm: Edit

Well i know for a banked curve tanx = v^2/(gr), hope that can help

 By Jason817 (Jason817) on Tuesday, October 21, 2003 - 07:41 pm: Edit

Thanks. Yeah I had just found that out.

 By Jason817 (Jason817) on Tuesday, October 21, 2003 - 09:35 pm: Edit

bump

 By Jason817 (Jason817) on Tuesday, October 21, 2003 - 11:06 pm: Edit

bump

 By Sup4 (Sup4) on Wednesday, October 22, 2003 - 09:52 am: Edit

for the second one equate the centepetal force to uN(u = coefficient of friction)

 By Jason817 (Jason817) on Wednesday, October 22, 2003 - 08:59 pm: Edit

thnx.

 By Jason817 (Jason817) on Saturday, October 25, 2003 - 09:06 pm: Edit

I still need help on #1 and the second part of #3. Plz!

 By Jason817 (Jason817) on Sunday, October 26, 2003 - 12:40 pm: Edit

bump

 By Jason817 (Jason817) on Sunday, October 26, 2003 - 01:47 pm: Edit

Also...

A mass 'm' is located in between the Earth and the Sun. If the mass experiences exactly the same attractice force due to the Earth as due to the Sun, where is it located?
a) 577 times closer to the Earth than the Sun
b) 2.59 x 10^8 meters from the earth
c) 1.497 x 10^11 meters from the Sun
d) All of the above
e) None of the above