91影视

A $10kg$box slides $4.0m$ down the frictionless ramp shown inFIGURE CP10.72, then collides with a spring whose spring constant is $250N/m$.

a. What is the maximum compression of the spring?

b. At what compression of the spring does the box have its maximum speed?

The spring in FIGURE CP10.73 has a spring constant of $1000N/m$. It is compressed $15cm$, then launches a $200g$block. The horizontal surface is frictionless, but the block鈥檚 coefficient of kinetic friction on the incline is $0.20$. What distance d does the block sail through the air?

A sled starts from rest at the top of the frictionless, hemispherical, snow-covered hill shown in FIGURE CP10.74.

a. Find an expression for the sled鈥檚 speed when it is at angle $蠒$.

b. Use Newton鈥檚 laws to find the maximum speed the sled can have at angle $蠒$without leaving the surface.

c. At what angle ${蠒}_{max}$does the sled 鈥渇ly off鈥� the hill?

A particle with the potential energy shown in FIGURE Q10.8 is moving to the right at x = 5 m with total energy E.

a. At what value or values of x is this particle鈥檚 speed a maximum?

b. Does this particle have a turning point or points in the range of x covered by the graph? If so, where?

c. If E is changed appropriately, could the particle remain at rest at any point or points in the range of x covered by the graph? If so, where?

What minimum speed does a 100 g puck need to make it to the top of a 3.0-m-long, 20掳 frictionless ramp?

A pendulum is made by tying a$500g$ball to a $75-cm-long$string. The pendulum is pulled$30掳$ to one side, then released. What is the ball鈥檚 speed at the lowest point of its trajectory?

A compressed spring launches a block up an incline. Which objects should be included within the system in order to make an energy analysis as easy as possible?