Splung.com Physics Forum
Discuss physics or ask questions. Part of the Splung.com physics web site.

Author Message
Delilah

Joined: 29 Mar 2010
Posts: 6
Location: Whiteville

 Posted: Tue Mar 30, 2010 8:23 pm    Post subject: Help Physics! A 1420-kilogram car, moving with a speed of 15.0 m/s, is on a flat, circular curve having a radius of 50.2 meters. How much friction is needed to keep the car on the road?___________N What is the coefficient of friction between the tires and the road?_______
hepcj

Joined: 23 Jun 2007
Posts: 125

 Posted: Tue Mar 30, 2010 10:29 pm    Post subject: m =1420 kg v= 15 m/s r = 50.2 The force pushing the radially outward is F = (m v^2)/r = 1420 x (15^2)/50.2 = 6364.54 N The car is kept on the track by the frictional force of the tyres opposing the centrifugal force F. The frictional force is related to the weight by F_fric = mu F_norm. where mu is the coefficient of friction. Since the car is on a horizontal track, the magnitude of the normal force is: F_norm = mg 1420 x 9.8 = 13916 N Therefore, the coefficient of friction = 6364.54 N/13916 N = 0.46
Delilah

Joined: 29 Mar 2010
Posts: 6
Location: Whiteville

 Posted: Wed Mar 31, 2010 1:35 am    Post subject: thanks so much, im having a time trying to grasp Physics
 Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First
 All times are GMT Page 1 of 1

 Jump to: Select a forum Physics Forum----------------Physics Help. Ask a Physics ExpertPast Papers
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum