Questions asked
David Collins
Numerade educator
Compare According to the periodic table, which two elements have an atomic mass less than twice their atomic number?
Bryan Valdivia
Which of the following correctly describes the structure of the typical eukaryotic genome? a. diploid b. linear c. singular d. double stranded
If the mean of five values is 64, find the sum of the values.
Linda Hand
(a) Use integration by parts to show that $$ \int f(x) d x=x f(x)-\int x f^{\prime}(x) d x $$ (b) If $f$ and $g$ are inverse functions and $f^{\prime}$ is continuous, prove that $$ \int_{a}^{b} f(x) d x=b f(b)-a f(a)-\int_{f(a)}^{(j)} g(y) d y $$ [Hint: Use part (a) and make the substitution $y=f(x) . ]$ (c) In the case where $f$ and $g$ are positive functions and $b>a>0,$ draw a diagram to give a geometric interpretation of part (b). (d) Use part (b) to cvaluate $\int_{1}^{c} \ln x d x$ .
Umar Sohail Qureshi
(I) In a mass spectrometer, germanium atoms have radii of curvature equal to 21.0, 21.6, 21.9, 22.2, and 22.8 cm. The largest radius corresponds to an atomic mass of 76 u. What are the atomic masses of the other isotopes?
Juan Nicolás
What effect will each of the following have on the demand for small automobiles such as the Mini Cooper and Smart car? a. Small automobiles become more fashionable. b. The price of large automobiles rises (with the price of small autos remaining the same). c. Income declines and small autos are an inferior good. d. Consumers anticipate that the price of small autos will greatly come down in the near future. e. The price of gasoline substantially drops.
Prabhat Tyagi
A woman stands at a horizontal distance $x$ from a mountain and measures the angle of elevation of the mountaintop above the horizontal as $\theta$ . After walking a distance $d$ closer to the mountain on level ground, she finds the angle to be $\phi$ . Find a general equation for the height $y$ of the mountain in terms of $d, \phi,$ and $\theta,$ neglecting the height of her eyes above the ground.
The graph below shows the distribution of molecular speeds for a gas at two different temperatures. (a) Does curve 1 or 2 better represent the behavior of the gas at the lower temperature? (b) Which curve represents the gas when it has a higher $\overline{E_{\mathrm{k}}} ?$ (c) Which curve is consistent with a higher diffusion rate?
(II) A 1.60 -kg object oscillates from a vertically hanging light spring once every 0.55 s. (a) Write down the equation giving its position $y(+$ upward) as a function of time $t,$ assuming it started by being compressed 16 $\mathrm{cm}$ from the equilibrium position (where $y=0 )$ , and released. $(b)$ How long will it take to get to the equilibrium position for the first time? (c) What will be its maximum speed? (d) What will be its maximum acceleration, and where will it first be attained?
The left end of a long glass rod 8.00 $\mathrm{cm}$ in diameter, with an index of refraction of $1.60,$ is ground and polished to a convex hemispherical surface with a radius of 4.00 $\mathrm{cm} .$ An object in the form of an arrow 1.50 $\mathrm{mm}$ tall, at right angles to the axis of the rod, is located on the axis 24.0 $\mathrm{cm}$ to the left of the vertex of the convex surface. Find the position and height of the image of the arrow formed by paraxial rays incident on the convex surface. Is the image erect or inverted?