A roller-coaster car has a mass of 508 kg when fully loaded with passengers. The path of the coaster from its initial point shown in the figure to point B involves only up-and-down motion (as seen by the riders), with no motion to the left or right. Assume the roller-coaster tracks at points @ and Bare parts of vertical circles of radius 1 = 10.0 m and 2 = 15.0 m, respectively. (a) If the vehicle has a speed of 19.9 m/s at point , what is the force exerted by the track on the car at this point? N b) What is the maximum speed the vehicle can have at ) and still remain on the track? m/s Submit Answer 2. [-/3 Points] DETAILS Consider a conical pendulum with a bob of mass m = 75.0 kg on a string of length L = 10.0 m that makes an angle of 8 = 4.00 with the vertical. (Consider +i to be towards the center of the circular path and +j to be upward.) (a) Determine the horizontal and vertical components of the force exerted by the string on the pendulum. Ni + Nj (b) Determine the radial acceleration of the bob. m/s2 Submit Answer 3. [-/4 Points] DETAILS An object of mass m = 0.440 kg is suspended from the ceiling of an accelerating truck as in the figure below. Take a = 2.60 m/s2. (a) Find the angle 8 (in degrees) that the string makes with the vertical. (b) Find the tension 7 (in N) in the string. N What If? The truck returns to a constant velocity so that the mass hangs straight down inside the truck, whereby 8 = 0. Later, the truck carefully slows down. During this braking maneuver, the string is observed to make a constant angle of 0 = 23.0 with the vertical. (c) What is the acceleration of the truck (in m/s2) while it is braking? m/s2 (d) What is the direction of the deflection of the string while the truck is braking? O forward O backward4. [-/2 Points] DETAILS MY NOTES A disk starts from rest and uniformly increases angular speed to 0.18 rev/s in 26 s. (a) What is its angular acceleration in radians per second per second? rad/s (b) Would doubling the angular acceleration during the given period have doubled final angular speed? O Yes O No Submit Answer 5. [-/2 Points] DETAILS MY NOTES An electric motor rotating a workshop grinding wheel at 1.14 x 10 rev/min is switched off. Assume the wheel has a constant negative angular acceleration of magnitude 2.10 rad/s. (a) How long does it take the grinding wheel to stop? (b) Through how many radians has the wheel turned during the time interval found in part (a)? rad Submit