Question

Constants A curve of radius 73 mis banked for a design speed of 90 km/h Part A If the coefficient of static friction is 0.30 (wet pavement), at what range of speeds can a car safely make the curve? (Hint: Consider the direction of the friction force when the car goes too slow or too fast.] Express your answers using two significant figures separated by a comma. EVO ALO ? Umin, Vmax= km/h Submit Request Answer < Return to Assignment Provide Feedback

Answer 1

elren: - r = 73 m V = 90 km/hr MB = 0.30 The equation for the rdeal velouty ma banked lun without triction is given by = Igrtane - tano Uz Uz gr gr Now v= 90 km 90 km 1000m X Ihr 360os hr hn 1 км J = 25 mis tant - ton" ((25) 2 625 716.13) 9.81 x 73 41.110 6€ angle of banking = Now, we have two equations for the banked turn with folution. One of the ear for maximum velouty is green by rgftane tus) W max 1 - Mstano and for the for the minimum veloury Dmin rg (tana - Ms) 1+ ustano

Vmax sgttant +Ms) 1 M8 tano 73x9.81 (tan 41:11 +0.30) I - 0.36 x tan (41.11% 33.73 m/s and Dmin rgltano - is) 1 + ustano = 73x9.81 (tan4111° -0.30) 1+0.30x tanu1.118 Vonin 18.03 mis There dese the veloury oo carshould be 18.03m so< 33.73 m S S Wmax 33.73 m/s Dmin = 18.08 m/s. 2 1km 360os 121.43 km 33.73 m Vmax = х Х hr 1000m 1km 36oos 64.91 km Umin X Х 18.03 m S hr 10oom Ihr