1
JEE Main 2023 (Online) 30th January Evening Shift
+4
-1 An electron accelerated through a potential difference $V_{1}$ has a de-Broglie wavelength of $\lambda$. When the potential is changed to $V_{2}$, its de-Broglie wavelength increases by $50 \%$. The value of $\left(\frac{V_{1}}{V_{2}}\right)$ is equal to
A
$\frac{3}{2}$
B
4
C
3
D
$\frac{9}{4}$
2
JEE Main 2023 (Online) 30th January Morning Shift
+4
-1 A small object at rest, absorbs a light pulse of power $$20 \mathrm{~mW}$$ and duration $$300 \mathrm{~ns}$$. Assuming speed of light as $$3 \times 10^{8} \mathrm{~m} / \mathrm{s}$$, the momentum of the object becomes equal to :

A
$$1 \times 10^{-17} \mathrm{~kg} \mathrm{~m} / \mathrm{s}$$
B
$$0.5 \times 10^{-17} \mathrm{~kg} \mathrm{~m} / \mathrm{s}$$
C
$$3 \times 10^{-17} \mathrm{~kg} \mathrm{~m} / \mathrm{s}$$
D
$$2 \times 10^{-17} \mathrm{~kg} \mathrm{~m} / \mathrm{s}$$
3
JEE Main 2023 (Online) 29th January Morning Shift
+4
-1

The threshold wavelength for photoelectric emission from a material is 5500 $$\mathop A\limits^o$$. Photoelectrons will be emitted, when this material is illuminated with monochromatic radiation from a

A. 75 W infra-red lamp

B. 10 W infra-red lamp

C. 75 W ultra-violet lamp

D. 10 W ultra-violet lamp

Choose the correct answer from the options given below :

A
C only
B
A and D only
C
C and D only
D
B and C only
4
JEE Main 2023 (Online) 25th January Evening Shift
+4
-1 Given below are two statements :

Statement I : Stopping potential in photoelectric effect does not depend on the power of the light source.

Statement II : For a given metal, the maximum kinetic energy of the photoelectron depends on the wavelength of the incident light.

In the light of above statements, choose the most appropriate answer from the options given below

A
Both Statement I and Statement II are incorrect
B
Statement I is correct but Statement II is incorrect
C
Both Statement I and Statement II are correct
D
Statement I is incorrect but Statement II is correct
JEE Main Subjects
Physics
Mechanics
Electricity
Optics
Modern Physics
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Physical Chemistry
Inorganic Chemistry
Organic Chemistry
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