Two banked curves have the same radius. curve a is banked at 12.7 °, and curve b is banked at an angle of 15.1°. a car can travel around curve a without relying on friction at a speed of 19.1 m/s. at what speed can this car travel around curve b without relying on friction?

20.88 m/s

Explanation:

Curve A:

theta = 12.7, vA = 19.1 m/s

Curve B:

Theta = 15.1 degree

Let the speed is v.

By the use of given formula

tanθ = v^2 / rg

For Curve A

tan 12.7 = (19.1)^2 / r g   (1)

For Curve B

tan 15.1 = v^2 / r g       (2)

Divide equation (2) by equation (1), we get

tan 15.1 / tan 12.7  = v^2 / (19.1)^2

0.269 / 0.225 = v^2 / 364.81

v = 20.88 m/s

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

snell's law

refractve index = sin incidence / sin refraction