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You are driving along a highway at 35.0 m/s when you hear the siren of a police car approaching you from behind and you perceive the frequency as 1390 Hz. You are relieved that he is in pursuit of a different speeder when he continues past you, but now you perceive the frequency as 1250 Hz. What is the frequency of the siren in the police car? The speed of sound in air is 343 m/s.

A single slit forms a diffraction pattern, with the first minimum at an angle of 40.0° from central maximum, using monochromatic light of 550-nm wavelength. What is the width of the slit?

An 18-mm wide diffraction grating has rulings of 650 lines per mm. Monochromatic light of 584 nm wavelength is incident normally on the grating. What is the largest angle, measured from the central bright spot, at which an intensity maximum is formed?

In a two-slit experiment, the slit separation is 2.20 × 10-5 m. The interference pattern is recorded on a flat screen-like detector that is 2.00 m away from the slits. If the seventh bright fringe on the detector is 10.0 cm away from the central fringe, what is the wavelength of the light passing through the slits?

In a two-slit experiment, the slit separation is 2.60 × 10-5 m. The interference pattern is recorded on a flat screen-like detector that is 2.00 m away from the slits. If the seventh bright fringe on the detector is 10.0 cm away from the central fringe, what is the wavelength of the light passing through the slits?

A sound source emits 31.0 W of acoustical power spread equally in all directions. The threshold of hearing is 1.0 × 10-12 W/m2. What is the sound intensity level 30.0 m from the source?

A single slit forms a diffraction pattern, with the first minimum at an angle of 40.0° from central maximum, using monochromatic light of 620-nm wavelength. What is the width of the slit?

You are driving along a highway at 35.0 m/s when you hear the siren of a police car approaching you from behind and you perceive the frequency as 1400 Hz. You are relieved that he is in pursuit of a different speeder when he continues past you, but now you perceive the frequency as 1290 Hz. What is the frequency of the siren in the police car? The speed of sound in air is 343 m/s.

The speed of light in a material is 0.52 c. What is the critical angle of a light ray at the interface between the material and a vacuum?

The tension in each of two strings is adjusted so that both vibrate at exactly 183 Hz. The tension in one of the strings is then increased slightly. As a result, six beats per second are heard when both strings vibrate. What is the new frequency of the string that was tightened?