Gamma rays are photons with very high energy. How many visible-light photons with a wavelength of 500 nm would you need to equal the energy of a gamma-ray photon with energy
A satellite of mass m has an orbital period T when it is in a circular orbit of radius R around the earth. If the satellite instead had mass 4m, its orbital period would be
Observer A sees a ruler moving by in a relativistic train and measures its length to be LA. Observer B moves together with the train and measures the length of the ruler to be LB. These two results will be such that
At a location where g = 9.80 m/s2, a projectile returns to its original height after 4.08 seconds, during which time it travels 76.2 meters horizontally. If air resistance can be neglected, what was the projectile's initial speed?
Suppose the first excited vibrational state of a molecule is at 1.50 eV. If the potential is close to that of a simple harmonic oscillator, the energy of the ground state is
Intensity of Sound: At a distance of 15.0 m from a sound source, the intensity level is 60.0 dB. What is the intensity level (in decibels) at a point 2.00 m from the source if the source radiates equally in all directions?
The siphon shown is used to transfer liquid from a higher level to a lower level. If the fluid is drawn up and is continuous through the tube, determine the velocity of flow of gasoline if the vertical distance from the liquid surface to the outlet is 1.0 m.<img src="https://sciemce.com/files/2/ppg__cognero__Chapter_15_Fluids.__media__a3d03e04-e7c2-4c6f-851c-96a4081e2ae1.PNG" style="vertical-align: 0px;" width="210px" height="250px" />
At what temperature would the root-mean-square speed of hydrogen, H2, molecules equal 11.2 km/s (the earth's escape speed)? The mass of a hydrogen atom is 1.67 × 10-27 kg, and the Boltzmann constant is 1.38 × 10-23 J/K
A hose has been clamped so that the area at the clamp is only one quarter the area of the rest of the hose. When we ignore the viscosity of water, the ratio of the volume of water delivered per unit time when the clamp is on to the volume of water delivered per unit time without the clamp is
A 400-g stainless steel tea kettle containing 500 g of water is on the stove. The portion of the tea kettle that is in contact with the heating element has an area of 0.090 m2 and is 2.0 mm thick
Graphical Analysis: The graph in the figure shows the position of a particle as it travels along the x-axis. What is the magnitude of the average velocity of the particle between t = 1.0 s and t = 4.0 s?<img src="https://sciemce.com/files/4/ppg__cp1pbb0313192044__f27g1q5g1.jpg" alt="" style="vertical-align: 0.0px;" height="304" width="351" />
Niobium metal becomes a superconductor (with electrical resistance equal to zero) when cooled below 9.00 K. If superconductivity is destroyed when the surface magnetic field exceeds 0.100 T, determine the maximum current a 5.31-mm-diameter niobium wire can carry and remain superconducting. (µ0 = 4π × 10^−7 T⋅m/A)
What is the minimum distance between two points on the Moon that could be just resolved by the Keck telescope in Hawaii using a wavelength of 600 nm and having perfect optics? The diameter of this telescope mirror system is 10 m, and the distance to
Four equal positive charges are placed at the corners of a square. The force on a +1 C charge placed at the center due to any single charge is 10 N. The value of the electric field at the center due to the charges at the corners is ________ N/C.
A proton, moving east, enters a magnetic field of a certain strength. Because of this field the proton curves downward. What is the direction of the magnetic field?
Energy Conservation With Conservative Forces: The figure shows a famous roller coaster ride. You can ignore friction. If the roller coaster leaves point Q from rest, what is its speed at the top of the 25-m peak (point S)<img src="https://sciemce.com/files/4/ppg__cp1pbb0313192044__f68g1q7g1.jpg" alt="" style="vertical-align: 0.0px;" height="131" width="300" />
Latent Heats: The figure shows a graph of the temperature of a pure substance as a function of time as heat is added to it at a constant rate in a closed container. If LF is the latent heat of fusion of this substance and LV is its latent heat of vaporization, what is the value of the ratio LV/LF?<img src="https://sciemce.com/files/4/ppg__cp1pbb0313192044__f171g1q1g1.jpg" alt="" style="vertical-align: 0.0px;" height="218" width="351" />
A centrifuge has a rotational inertia of <img src="https://sciemce.com/files/4/c845c22a0633e85519.png" class="w-image" />How much energy must be supplied to bring it from rest to 500 rad/s?
Five children are pushing on a snowball; each is pushing with a force of 10.0 N. Each is pushing at an angle of 45<img src="https://sciemce.com/files/4/7ea1d94e9b13463337.png" class="w-image" />relative to his neighbor. What is the net push on the ball?
A rock is rolled in the sand. It starts at 5.0 m/s, moves in a straight line for a distance of 6.0 m, and then stops. What is the magnitude of the average acceleration?
Mass on a Spring: In a supermarket, you place a 22.3-N (around 5 lb) bag of oranges on a scale, and the scale starts to oscillate at 2.7 Hz. What is the force constant (spring constant) of the spring of the scale?
A 500-kg elevator is pulled upward with a constant force of 5500 N for a distance of 50.0 m. (a) What is the work done by the 5500-N force? (b) What is the work done by gravity? (c) What is the net work done on the elevator?
Standing Waves on a String: The speed of propagation of a transverse wave on a 2.0-m long string fixed at both ends is 200 m/s. Which one of the following is not a resonant frequency of this string?
Charge of uniform linear density (4.0 nC/m) is distributed along the entire x axis. Determine the magnitude of the electric field on the y axis at y = 2.5 m.
A uniform sphere of radius R and mass M rotates freely about a horizontal axis that is tangent to an equatorial plane of the sphere, as shown below. The rotational inertia of the sphere about this axis is
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