CUET · PHYSICS · PYQ PAPER 2023
The half-lives of two radioactive specimens are \(T_1=5\) years and \(T_2=7.5\) years.
The ratio of their disintegration constants \(\lambda_1\) and \(\lambda_2\) is:
- A \(\frac{3}{2}\)
- B \(\frac{2}{3}\)
- C 1: 1
- D 0.693
Answer & Solution
Correct Answer
(A) \(\frac{3}{2}\)
Step-by-step Solution
Detailed explanation
\( \lambda = \frac{\ln(2)}{T} \) \( \frac{\lambda_1}{\lambda_2} = \frac{T_2}{T_1} \) \( \frac{\lambda_1}{\lambda_2} = \frac{7.5}{5} = \frac{3}{2} \)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from PHYSICS
- Match List-I with List-II
List-I
(Electronic Device)List-II
(Function)(A) Stabilizer (I) Used to convert a.c. voltage into d.c. voltage (B) Filter (II) Used either for stepping up or stepping down the a.c. voltage (C) Rectifier (III) Used for constant output voltage even when the input voltage or load current changes (D) Transformer (IV) Used to remove any ripple in the rectified output voltage
Choose the correct answer from the options given below:CUET 2025 Easy - Match List-I with List-II
List-I (Electromagnetic Wave Wave) List-II (Application) (A) Microwaves (I) Photographs during foggy season and night vision cameras (B) X-rays (II) Radar (C) Gamma rays (III) Photographs internal parts of human body (D) Infrared Rays (IV) Radiography for malignant tumors in cancer treatment
Choose the correct answer from the options given below:CUET 2025 Medium - A bar magnet held perpendicular to a uniform magnetic field experiences a torque \( T_1 \). By what angle should it be rotated to change the experienced torque to \( 0.5T_1 \)?CUET 2025 Easy
- An electric dipole is placed in a non-uniform electric field, such that the dipole moment is parallel to the electric field. The dipole will experienceCUET 2025 Medium
- Choose a vector quantity from the following:CUET 2025 Hard
- A straight wire of mass 200 g and length 1.5 m carrying a current of 2 A is placed in a uniform magnetic field at right angles to its direction, is suspended in mid air. The magnitude of magnetic field is : \(\left(g=9.8 m / s ^2\right)\)CUET 2023 Hard
More PYQs from CUET
- Identify the incorrect statements with reference to dispersion of white light.
(A) Red light gets most deviated while passing through the prism.
(B) Thick lenses show chromatic aberrations due to dispersion.
(C) Refractive index of medium for different colours is different.
(D) Red light travels faster than violet light in the prism.
(E) While light, once dispersed, cannot be recombined.
Choose the correct answer from the options given below :CUET 2023 Medium - Resonant frequency of a LCR series circuit is 16 kHz. If the capacitance is increased to 16 times, then the new resonant frequency will becomeCUET 2025 Easy
- A die is rolled in such a way that an even number is twice likely to occur as an odd number.
If the die is rolled twice, then the mean of the number of perfect squares in two tosses is :CUET 2025 Easy - A student is asked to observe his face in three different types of mirrors P, Q, R one by one by holding each mirror close to his face at same distance. Mirror P given exact and same size image, Q gives exact but smaller while R gives exact but larger image.
A. P is Convex mirror, Q is Plane, R is Concave
B. P is Plane, Q is Convex, R is Concave
C. P is Concave, Q is Plane, R is Convex
D. P is Convex, Q is Concave, R is Plane
Choose the correct answer from the options given below:CUET 2023 Medium - Which of the following structures are related to the male reproductive organ.
(A). Isthmus
(B). Sertoli cells
(C). Leydig cells
(D). Prostate
Choose the correct answer option given below.CUET 2025 Medium - Out of the given statement, choose the correct statement.
(A) The direction ratios of the vector \(\vec{a}=3 \hat{i}-\hat{j}+4 \hat{k}\) is \(3,-1,4\).
(B) If \(\theta\) is the angle between two vectors \(\vec{a}\) and \(\vec{b}\), then their cross product is given as \(\vec{a} \times \vec{b}=|\vec{a}||\vec{b}| \cos \theta\).
(C) The unit vector in the direction of vector \(\vec{a}=\hat{i}+2 \hat{j}-2 \hat{k}\) is \(\hat{a}=\frac{1}{3}(\hat{i}+2 \hat{j}-2 \hat{k})\).
(D) If \(\vec{a}=3 \hat{i}\) and \(\vec{b}=4 \hat{j}\) then \(\vec{a} \cdot \vec{b}=12\).
(E) If \(\vec{a}\) and \(\vec{b}\) represent the adjacent sides of a triangle then its area is given of \(\frac{1}{2}|\vec{a} \times \vec{b}|\).
Choose the correct answer from the options given below :CUET 2023 Hard