Consider a helium (He) atom that absorbs a photon of wavelength 330 nm. The change in the velocity (in cm s-1) of the He atom after the photon absorption is_____.
(Assume: Momentum is conserved when the photon is absorbed.
Use: Planck constant = 6.6 × 10-34 J s, Avogadro number = 6 × 1023 mol-1, Molar mass of He = 4 g mol-1)
(Assume: Momentum is conserved when the photon is absorbed.
Use: Planck constant = 6.6 × 10-34 J s, Avogadro number = 6 × 1023 mol-1, Molar mass of He = 4 g mol-1)
Correct Answer: 30
Solution and Explanation
Change in velocity of He-atoms = 30 cm s-1
Top Questions on Atomic Models
- Choose the Incorrect Statement about Dalton's Atomic Theory
- JEE Main - 2024
- Chemistry
- Atomic Models
- Magnetic moment due to the motion of the electron in nth orbit of Bohr atom is proportional to nx. The value of x is
- JEE Main - 2024
- Chemistry
- Atomic Models
Identify the correct statements about alkali metals
A. The order of standard reduction potential $\left( M ^{+} \mid M \right)$ for alkali metal ions is $Na > Rb > Li$.
B. $CsI$ is highly soluble in water.
C. Lithium carbonate is highly stable to heat.
D. Potassium dissolved in concentrated liquid ammonia is blue in colour and paramagnetic.
E. All the alkali metal hydrides are ionic solids.
Choose the correct answer from the options given below:- JEE Main - 2023
- Chemistry
- Atomic Models
- Assume that the radius of the first Bohr orbit of hydrogen atom is $0.6Å$. The radius of the third Bohr orbit of $He^+$is _______ picometer. (Nearest Integer)
- JEE Main - 2023
- Chemistry
- Atomic Models
Electrons in a cathode ray tube have been emitted with a velocity of $1000\, m s ^{-1}$ The number of following statements which is/are true about the emitted radiation is _______ Given : $h =6 \times 10^{-34} J s , m _e=9 \times 10^{-31} kg$
(A) The deBroglie wavelength of the electron emitted is $66667 nm$
(B) The characteristic of electrons emitted depend upon the material of the electrodes of the cathode ray tube
(C) The cathode rays start from cathode and move towards anode
(D) The nature of the emitted electrons depends on the nature of the gas present in cathode ray tube
- JEE Main - 2023
- Chemistry
- Atomic Models
Questions Asked in JEE Advanced exam
- Consider the ellipse \(\frac{x^2}{9}+\frac{y^2}{4}=1\). Let S (p, q) be a point in the first quadrant such that \(\frac{p^2}{9}+\frac{q^2}{4}>1\). Two tangents are drawn from S to the ellipse, of which one meets the ellipse at one end point of the minor axis and the other meets the ellipse at a point T in the fourth quadrant. Let R be the vertex of the ellipse with positive x-coordinate and Obe the center of the ellipse. If the area of the triangle △ORT is \(\frac{3}{2}\) , then which of the following options is correct ?
- JEE Advanced - 2024
- Conic sections
- Among V(CO)6, Cr(CO)5, Cu(CO)3, Mn(CO)5, Fe(CO)5, [Co(CO)3]3-, [Cr(CO)4]4-, and Ir(CO)3, the total number of species isoelectronic with Ni(CO)4 is _________.
[Given, atomic number: V = 23, Cr=24, Mn 25, Fe 26, Co 27, Ni 28, Cu = 29, Ir = 77]- JEE Advanced - 2024
- Isomerism in Coordination Compounds
- Let \(\overrightarrow{OP}=\frac{\alpha-1}{\alpha}\hat{i}+\hat{j}+\hat{k},\overrightarrow{OQ}=\hat{i}+\frac{\beta-1}{\beta}\hat{j}+\hat{k}\) and \(\overrightarrow{OR}=\hat{i}+\hat{j}+\frac{1}{2}\hat{k}\) be three vector where α, β ∈ R - {0} and 0 denotes the origin. If \((\overrightarrow{OP}\times\overrightarrow{OQ}).\overrightarrow{OR}=0\) and the point (α, β, 2) lies on the plane 3x + 3y - z + l = 0, then the value of l is _______.
- JEE Advanced - 2024
- Vector Algebra
- A closed vessel contains 10 g of an ideal gas X at 300 K, which exerts 2 atm pressure. At the same temperature, 80 g of another ideal gas Y is added to it and the pressure becomes 6 atm. The ratio of root mean square velocities of X and Y at 300 K is
- JEE Advanced - 2024
- States of matter
- Let the function \(f:[1,\infin)→\R\) be defined by
\(f(t) = \begin{cases} (-1)^{n+1}2, & \text{if } t=2n-1,n\in\N, \\ \frac{(2n+1-t)}{2}f(2n-1)+\frac{(t-(2n-1))}{2}f(2n+1) & \text{if } 2n-1<t<2n+1,n\in\N. \end{cases}\)
Define \(g(x)=\int\limits_{1}^{x}f(t)dt,x\in(1,\infin).\) Let α denote the number of solutions of the equation g(x) = 0 in the interval (1, 8] and \(β=\lim\limits_{x→1+}\frac{g(x)}{x-1}\). Then the value of α + β is equal to _____.- JEE Advanced - 2024
- Integral Calculus