A hydrogen atom in its ground state absorbs 10.2 eV of energy. The angular momentum of electron of the hydrogen atom will increase by the value of: (Given, Planck’s constant = \(6.6 × 10^{–34}\) Js).
\(2.10 × 10^{–34}\) Js
- \(1.05 × 10^{–34}\) Js
- \(3.15 × 10^{–34}\) Js
- \(4.2 × 10^{–34}\) Js
The Correct Option is B
Solution and Explanation
\(-13.6+10.2=\frac{-13.6}{n^2}\)
\(⇒ \frac{13.6}{n^2} = 3.4\)
\(⇒ n = 2\)
\(⇒ Δ L = 2 \times \frac{h}{2λ} - 1 \times \frac{h}{2λ}\)
\(⇒ \frac{h}{2λ}\)
\(⇒ Δ L ≅ 1.05 \times 10^{-34} \;J\;s\)
Hence, the correct option is (B): \(1.05 × 10^{–34}\) \(J s\)
Top Questions on momentum
Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Knowing the initial position \( x_0 \) and initial momentum \( p_0 \) is enough to determine the position and momentum at any time \( t \) for a simple harmonic motion with a given angular frequency \( \omega \).
Reason (R): The amplitude and phase can be expressed in terms of \( x_0 \) and \( p_0 \).
In the light of the above statements, choose the correct answer from the options given below:- The principle involved in the performance of a circus acrobat is the conservation of
- KEAM - 2024
- Physics
- momentum
- A particle moves under the influence of a force in the XY-plane such that the components of its linear momentum $\vec{p}$ at any time $t$ are given by $p_x = p \sin t$ and $p_y = p \cos t$. The angle between $\vec{F}$ and $\vec{p}$ at that time is
- KEAM - 2024
- Physics
- momentum
- Given below are two statements:
Statement (I): Planck's constant and angular momentum have the same dimensions.
Statement (II): Linear momentum and moment of force have the same dimensions.
In the light of the above statements, choose the correct answer from the options given below: - The magnetic moment of an electron (e) revolving in an orbit around the nucleus with an orbital angular momentum is given by:
Questions Asked in JEE Main exam
- Suppose that the number of terms in an A.P. is \( 2k, k \in \mathbb{N} \). If the sum of all odd terms of the A.P. is 40, the sum of all even terms is 55, and the last term of the A.P. exceeds the first term by 27, then \( k \) is equal to:
- JEE Main - 2025
- Arithmetic Progression
- Two iron solid discs of negligible thickness have radii \( R_1 \) and \( R_2 \) and moment of inertia \( I_1 \) and \( I_2 \), respectively. For \( R_2 = 2R_1 \), the ratio of \( I_1 \) and \( I_2 \) would be \( \frac{1}{x} \), where \( x \) is:
- JEE Main - 2025
- System of Particles & Rotational Motion
- Given below are two statements:
Statement (I): Corrosion is an electrochemical phenomenon in which pure metal acts as an anode and impure metal as a cathode.
Statement (II): The rate of corrosion is more in alkaline medium than in acidic medium.
In the light of the above statements, choose the correct answer from the options given below:- JEE Main - 2025
- Electrochemistry
- The number of solutions of the equation \[ \left( \frac{9}{x} - \frac{9}{\sqrt{x}} + 2 \right) \left( \frac{2}{x} - \frac{7}{\sqrt{x}} + 3 \right) = 0 \] is:
- JEE Main - 2025
- permutations and combinations
- Let \( (2, 3) \) be the largest open interval in which the function \( f(x) = 2 \log_e (x - 2) - x^2 + ax + 1 \) is strictly increasing, and \( (b, c) \) be the largest open interval, in which the function \( g(x) = (x - 1)^3 (x + 2 - a)^2 \) is strictly decreasing. Then \( 100(a + b - c) \) is equal to:
- JEE Main - 2025
- Quadratic Equations
Concepts Used:
Momentum
It can be defined as "mass in motion." All objects have mass; so if an object is moving, then it is called as momentum.
the momentum of an object is the product of mass of the object and the velocity of the object.
Momentum = mass • velocity
The above equation can be rewritten as
p = m • v
where m is the mass and v is the velocity.
Momentum is a vector quantity and the direction of the of the vector is the same as the direction that an object.