Spring Compression

A small block of mass 0.09 kg is placed against a compressed spring at the bottom of a frictionless track that slopes upward at an angle of 40* above the horizontal. The spring has k=640 N/m and negligible mass. When the spring is released, the block travels a maximum distance of 1.8 m along the track before sliding back down. Before reaching this maximum distance, the block loses contact with the spring. A. What distance was the spring originally compressed? B. When the block has traveled along the track 0.8 m from its initial position against the compressed spring, is it still in contact with the spring? What is the kinetic energy of the block at this point?

Work-Energy Theorem

A car is traveling on a level road with speed vi at the instant when the brakes lock, so that all the tires slide rather than roll. A. Use the work-energy theorem to calculate the minimum stopping distance of the car in terms of vi and g and the coefficient of kinetic friction, "mu"of"k" between the tires and the road. B. The car stops in a distance of 90 m if vi=80 km/h. What is the stopping distance if vi is 60 km/h. Assume that the value of "mu"of"k" remains the same.

Springs and Slopes

A spring of constant k, compressed a distance x, is used to launch a mass m up a frictionless slope that makes an angle "theta" with the horizontal. Find an expression for the maximum distance along the slope that the mass moves after leaving the spring? How is the expression modified when you include kinetic friction in the problem?

Energy Stored in a Spring

The force exerted by an unusual spring when it is compressed a distance x from equilibrium is given by F = -kx-cx^3, where k=220 N/m and c=3.6 N/m^3. Find the energy stored in this spring when it has been compressed by 15 cm.

Tidal power

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