BackFIGURE P39.28 shows a pulse train. The period of the pulse train is T = 2 Δt, where Δt is the duration of each pulse. What is the maximum pulse-transmission rate (pulses per second) through an electronics system with a 200 kHz bandwidth? (This is the bandwidth allotted to each FM radio station.)
How much energy would be required to break a helium nucleus into its constituents, two protons and two neutrons? The rest masses of a proton (including an electron), a neutron, and neutral helium are, respectively, 1.00783 u, 1.00867 u, and 4.00260 u. (This energy difference is called the total binding energy of the nucleus.)
A pesky -mg mosquito is annoying you as you attempt to study physics in your room, which is m wide and m high. You decide to swat the bothersome insect as it flies toward you, but you need to estimate its speed to make a successful hit.
(a) What is the maximum uncertainty in the horizontal position of the mosquito?
(b) What limit does the Heisenberg uncertainty principle place on your ability to know the horizontal velocity of this mosquito? Is this limitation a serious impediment to your attempt to swat it?
A hydrogen atom has orbital angular momentum 3.65 × 10⁻³⁴ J s. What is the atom's minimum possible energy? Explain.
An astronaut travels to a star system 4.5 ly away at a speed of 0.90c. Assume that the time needed to accelerate and decelerate is negligible. How long does the journey take according to Mission Control on earth?
Which of the following objects provides an inertial frame of reference?
In the context of inertial reference frames, what does the definition of a frame of reference primarily rely on?
Which of the following statements correctly describes an inertial reference frame?
Which statement best describes the role of a frame of reference in describing motion?
A particle in a box is a billiard ball ( kg) and the box has a width of m, the size of a billiard table. (Assume that the billiard ball slides without friction rather than rolls; that is, ignore the rotational kinetic energy.) What is the difference in energy between the and levels? Are quantum mechanical effects important for the game of billiards?
Which of the following best defines an inertial reference frame?
Which of the following best describes a reference frame in physics?
(a) The -coordinate of an electron is measured with an uncertainty of mm. What is the x-component of the electron's velocity, , if the minimum percent uncertainty in a simultaneous measurement of is ?
(b) Repeat part (a) for a proton.
An electron confined in a one-dimensional box is observed, at different times, to have energies of 12 eV, 27 eV, and 48 eV. What is the length of the box?
Photoelectrons are observed when a metal is illuminated by light with a wavelength less than 388 nm. What is the metal's work function?