91Ó°ÊÓ

Find the length (in \(\mathrm{m}\) ) of a pendulum with a period of \(0.700 \mathrm{~s}\).

Find the wavelength of water waves with frequency \(0.650 \mathrm{~Hz}\) and velocity \(1.50 \mathrm{~m} / \mathrm{s}\).

A sound wave is transmitted through water from one submarine, is reflected off another submarine \(15 \mathrm{~km}\) away, and returns to the sonar receiver on the first submarine. What is the round-trip transit time for the sound wave? Assume that the water temperature is \(25^{\circ} \mathrm{C}\).

A sonar receiver detects a reflected sound wave from another ship \(3.52 \mathrm{~s}\) after the wave was transmitted. How far away is the other ship? Assume that the water temperature is \(25^{\circ} \mathrm{C}\).

What is the wavelength of longitudinal waves in a coil spring with frequency \(7.50 \mathrm{~Hz}\) and velocity \(6.10 \mathrm{~m} / \mathrm{s}\) ?

A wave generator produces 20 pulses in \(3.50 \mathrm{~s}\). (a) What is its period? (b) What is its frequency?

Find the frequency of a wave produced by a generator that emits 30 pulses in \(2.50 \mathrm{~s} .\)

If you double the length of a pendulum, what happens to its period?

A train traveling at a speed of \(4 \overline{0} \mathrm{~m} / \mathrm{s}\) approaches an observer at a station and sounds a \(55 \overline{0}\) -Hz whistle. What frequency will be heard by the observer? Assume that the sound velocity in air is \(345 \mathrm{~m} / \mathrm{s}\).

What is the wavelength of an electromagnetic wave with frequency \(50.0 \mathrm{MHz}\) ?