Figure CQ10.13

You are riding your bicycle down the street at a speed of 16 m/s. Your bicycle's frame has a mass of 6.0 kg, and each of its two wheels has mass 2.2 kg and radius 0.34 m. Each wheel can be thought of as a hollow hoop (assuming that the rim has much larger mass than the spokes). What is the total kinetic energy of the bicycle (in Joules), taking into account both the translational and rotational motion?

A hula hoop (which can be modeled as a solid hoop) rolls without slipping across the floor. Observing the motion of its center of mass, you find that it has a translational kinetic energy of 2.42 J. What is its rotational kinetic energy (in Joules) about an axis passing through its center of mass?

A baseball has a mass of 0.15 kg and radius 3.7 cm. In a baseball game, a pitcher throws the ball with a substantial spin so that it moves with an angular speed of 41 rad/s and a linear speed of 34 m/s. Assuming the baseball to be a uniform solid sphere, determine the rotational and translational kinetic energies of the ball in joules. KErotational = KE translational =

A bicycle wheel with a radius of 350 mm and a mass of (2.40x10^0) kg is spinning freely on a work stand at a rate of 2.0 rev/sec when a (1.0000x10^0) kg kitten jumps on it radially, holds on and starts spinning around. What is the new rotational velocity of the wheel in units of rev/s? Treat the wheel as a thin hoop. Give your answer with three significant figures.

A solid ball (sphere) of mass 1 kg and radius 0.3 m is held at rest at the top of a ramp. There is enough friction so that the ball will roll down the ramp without slipping. The top of the ramp is 10 meters above the ground.What will the speed be of the ball just before it hits the bottom of the ramp?

You are trying to get a better feel for the effect of geometry and mass distribution on the moment of inertia. You have a solid disk and a thin ring, each of radius, r = 1.30 m, and mass, m = 73.0 kg. You mount both on fixed, horizontal frictionless axes about which they can spin freely. Then you spin them both. (a) How much work do you need to do to get each object to spin at 3.00 rad/s? (b) Let us assume that you have been causing them to spin by using a constant force applied tangentially to their circumferences. If the above speed is to be reached within 0.700 s, what is the magnitude of the force you need to apply to each object? (c) You next attempt to stop each object by pressing one finger on each side of each object, right at the outer edge. The coefficient of kinetic friction between each finger and the surface of each object is 0.300. Find the minimum force you have to apply to stop each object within 1.00 min.

A thin, 20-gram hoop with a radius of 2 meters is rolling without slipping, initially along a level surface, with its center of mass moving at 20 m/s and with a rotation rate about that center of mass of 10 rad/s. Then it rolls up an incline, coming to rest (momentarily) as shown below. В Vcm =0 m/s Wcm=0 rad/s Wcm=10rad/s h Vcm = 10m/s A Below is the work-energy equation with all the forms of energy we have discussed up to now. Which of these energy terms are zero? ΔΕhem+ΔΚΕ+ ΑΚΕΡ+ Δυ Δυ ΔΕ ound ΔΕ Wext