Explore BrainMass


PROBLEM 1. When a car accelerates, the normal force at the tire/ground interface changes, increasing at the rear tires and decreasing at the front. Does the same occur for the Batmobile? The Batmobile is shown, along with its jet-engine propulsion system (please see the attachment). Assume an acceleration of 0.9g. Neglect ground/tire forces in the i direction. L1 = 1m, L2 = 1.8m, and h = 0.65m.

How do the normal forces change from their static values?

PROBLEM 2. A gymnast competing at the Olympics is performing a routine on the uneven bars. After completing a flip, she approaches the higher of the two bars with a speed v0 at an angle beta; with respect to the ground. Assume that her body is aligned with the horizontal at approach. The gymnast has a mass m, and her body has a length of L with her hands and legs stretched out. Find the gymnast's angular speed just after grabbing on to the bar?

PROBLEM 3. A hoop with mass m = 10kg and radius r = 0.4m is rolled down a rough surface toward a spring of stiffness k = 1500N/m. The surface is angled at 45 degree with respect to the horizontal, and the hoop's mass center G is initially d = 4m from the spring. The hoop rolls without slip down the incline, and its moment of inertia about G is IG = mr^2. Find the initial speed v0 of the hoop's mass center if the maximum compression of the spring is 0.7m?

(Please see the attachment for figs.)


Solution Summary

Step by step solutions provided.