Identify the invalid Python statement from the following:
Show Hint
d = dict()
e = {}
f = []
g = dict{}
The Correct Option is D
Solution and Explanation
The statement g = dict{} is invalid because the dict() function should not include curly braces {} as an argument. The correct way to initialize an empty dictionary is g = dict() or g = {}. All other options correctly initialize dictionaries or lists.
Top Questions on Commands and Requests
Write a user-defined function in Python named showGrades(S) which takes the dictionary
Sas an argument. The dictionaryScontains Name: [Eng, Math, Science] as key:value pairs.
The function displays the corresponding grade obtained by the students according to the following grading rules:
\[ \begin{array}{|c|c|} \hline \textbf{Average of Eng, Math, Science} & \textbf{Grade} \\ \hline \geq 90 & A \\ \hline < 90 \text{ but } \geq 60 & B \\ \hline < 60 & C \\ \hline \end{array} \]
Example: Consider the following dictionary: \[ S = \{\text{"AMIT"}: [92, 86, 64], \text{"NAGMA"}: [65, 42, 43], \text{"DAVID"}: [92, 90, 88]\} \] The output should be: \[ \text{AMIT} - B \\ \text{NAGMA} - C \\ \text{DAVID} - A \]- CBSE CLASS XII - 2024
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- The slicing operations in the given code work as follows:
myStr[:4]extracts the first 4 characters, which are"MISS".myStr[-5:]extracts the last 5 characters, which are"SIPPI".- These two substrings are concatenated with a
"#"in between, resulting in"MISS#SIPPI".
- CBSE CLASS XII - 2024
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- Question: Select the correct output of the following code:
event = "G20 Presidency@2023" L = event.split(' ') print(L[::-2])- CBSE CLASS XII - 2024
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- State whether the following statement is True or False:
While handling exceptions in Python, name of the exception has to be compulsorily added with except clause.- CBSE CLASS XII - 2024
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Consider the following Python statement:
F = open('CONTENT.TXT')
Which of the following is an invalid statement in Python?
- CBSE CLASS XII - 2024
- Computer Science
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Questions Asked in CBSE CLASS XII exam
- A point source of light in air is kept at a distance of 12 cm in front of a convex spherical surface of glass of refractive index 1.5 and radius of curvature 30 cm. Find the nature and position of the image formed.
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- Ray optics and optical instruments
- Two slits 0.1 mm apart are arranged 1.20 m from a screen. Light of wavelength 600 nm from a distant source is incident on the slits.
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- Wave optics
- Two infinitely long straight wires ‘1’ and ‘2’ are placed \(d\) distance apart, parallel to each other, as shown in the figure. They are uniformly charged having charge densities \(\lambda\) and \(-\frac{\lambda}{2}\) respectively. Locate the position of the point from wire ‘1’ at which the net electric field is zero and identify the region in which it lies.
- CBSE CLASS XII - 2025
- Electrostatics
Standard electrode potential for \( \text{Sn}^{4+}/\text{Sn}^{2+} \) couple is +0.15 V and that for the \( \text{Cr}^{3+}/\text{Cr} \) couple is -0.74 V. The two couples in their standard states are connected to make a cell. The cell potential will be:
To calculate the cell potential (\( E^\circ_{\text{cell}} \)), we use the standard electrode potentials of the given redox couples.
Given data:
\( E^\circ_{\text{Sn}^{4+}/\text{Sn}^{2+}} = +0.15V \)
\( E^\circ_{\text{Cr}^{3+}/\text{Cr}} = -0.74V \)- CBSE CLASS XII - 2025
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A carpenter needs to make a wooden cuboidal box, closed from all sides, which has a square base and fixed volume. Since he is short of the paint required to paint the box on completion, he wants the surface area to be minimum.
On the basis of the above information, answer the following questions :
Find a relation between \( x \) and \( y \) such that the surface area \( S \) is minimum.- CBSE CLASS XII - 2025
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