1. A mass of 7.8 kg is attached to a spring and free to oscillate without friction. The observed frequency of vibration is 1.1 Hz. What will be the frequency of vibration when a new mass of 8.8 kg is attached to the same spring and set to vibrate?

2. A mass-spring system requires 1.8 joules of work to compress the spring by 27.5 cm. When released the maximum acceleration is observed to be 47 m/s². (a) Determine the value of the mass.