Practical 2 - Laws of Motion Part B Aim To introduce concepts related to forces including vectors, the line of action of a force and adding and subtracting forces. To introduce the concept of friction and the factors that affect the magnitude of friction forces. Friction is the resistance to movement between two surfaces in contact. The direction of the friction force is always opposite to the motion between the two surfaces. Friction is dependent on the surfaces involved, the applied force (perpendicular to the surface; a "normal" force) and whether the surfaces are stationary or moving.

5. Calculate the displacement of a sine wave in mm of Time Period of 2 seconds and amplitude 8 cm, 0.3(2)seconds after the commencement of the wave.

2) Light with a wavelength of 2000 Å is incident upon a metal that has a work function of 1.9eV. What is the maximum kinetic energy of the escaped electron?

Problem 39. Repeat Problem 38 if µ1 =0.5 kg/m and µ2=0.2kg/m.

Question 3, How does the amplitude with only one wave compare to that with two waves superposed with no phase difference? Support your observation using the concept of interference. g) Record your observations on how the wave pattern changes as you increase the phase difference to 180 degrees.

3) Electrons are ejected from a certain metal only when the wavelength of incident light is less than or equal to 4000 Å. What wavelength would be required to eject some electrons with a kinetic energy of 2 eV from this metal?

Compute the material dispersion for a wavelength 10 nm lower than the zero-dispersion wavelength (assumed to be 1300 nm).

5. A train approaches a station and sounds its horn which has a natural frequency of 150Hz. The train is travelling at 40 m/s and the speed of sound in air is 340 m/s. a. What frequency does a person standing at the station hear? (10 points) b. What frequency does a person sitting on the train hear? (10 points)

Find the intensity (in W/m²) of a 58.0 dB sound. Find the intensity (in W/m²) of a 96.0 dB sound.

Consider a mass m on a spring in the presence of damping, such that b/m = wo/5, where b is the damping constant and wo the natural angular frequency. a) Show that this system is underdamped. b) What is the oscillation frequency w of the system? c) By how much does the amplitude decrease after one cycle? 1) Consider the same damped oscillator, but now also with a periodic driving force. How does its amplitude at a driving frequency wa that is 10% above wo compare to its resonance amplitude (amplitude at wa= wo)? Express your answer as a percentage.