Ch 11 Section 1 Objectives We will learn Hooke’s Law Harmonic Motion How to calculate the period for a pendulum and spring and How to calculate the speed of a wave. Warm-Up Find the units for k in Hooke’s Law. The formula is: – F= -kx – F is force in Newtons – And x stands for displacement in meters
Practice If a mass of 0.55 kg attached to a vertical spring stretches the spring 2.0 cm from its original equilibrium position, what is the spring constant? A 76 N crate hung from a spring (k=450). How much displacement is caused by the weight of the crate? A spring (k=1962) loses elasticity if stretched more than 50cm. What is the mass of the heaviest object the spring can support without damage?
Exit Ticket HW: ….Turn in Next day as Quiz Grade. It will be handed back Friday
Lab Objectives We will learn Hooke’s Law Harmonic Motion How to calculate the period for a pendulum and spring and How to calculate the speed of a wave. Warm-Up Turn in HW as a grade
Lab and Exit Ticket You will write a formal lab report to calculate the spring constant of several springs. Each student is required to complete the math for one spring. You will need to complete the following: – Objective: – Materials: – Procedure: – Data Table: – Analysis/Conclusion: This is the math
Ch 11 Section 2 Objectives We will learn Hooke’s Law Harmonic Motion How to calculate the period for a pendulum and spring and How to calculate the speed of a wave. Warm-Up Get out HW
Practice You need to know the height of a tower, but darkness obscures the ceiling. You note that a pendulum extending from the ceiling almost touches the floor and that its period is 12 s. How tall is the tower? What is the period of a 3.98m long pendulum? What is the period of a 99.4cm long pendulum?
Exit Ticket HW:
Ch 11 Section 2 Objectives We will learn Hooke’s Law Harmonic Motion How to calculate the period for a pendulum and spring and How to calculate the speed of a wave. Warm-Up Get out HW
Practice The body of a 1275 kg car is supported on a frame by four springs. Two people riding in the car have a combined mass of 153 kg. When driven over a pothole in the road, the frame vibrates with a period of s. For the first few seconds, the vibration approximates simple harmonic motion. Find the spring constant of a single spring. A 1kg mass attached to one end of a spring completes on oscillation every 2 seconds. K=?
Exit Ticket HW:
Ch 11 Section 3 Objectives We will learn Hooke’s Law Harmonic Motion How to calculate the period for a pendulum and spring and How to calculate the speed of a wave. Warm-Up Get out HW
Waves require an environment to travel through-these are called mechanical waves and the environment is the medium – Transverse- rope particles vibrate perpendicular – Longitudinal- spring particles vibrate parallel
Practice A piano string tuned to middle C vibrates with a frequency of 262 Hz. Assuming the speed of sound in air is 343 m/s, find the wavelength of the sound waves produced by the string
Exit Ticket HW: Complete #2 in the procedure for the Lab on Pg 402
Lab Objectives We will learn Hooke’s Law Harmonic Motion How to calculate the period for a pendulum and spring and How to calculate the speed of a wave. Warm-Up Turn in HW as a grade Complete Lab on Page 402