The JEE Main exam is a crucial step for students aspiring to enter prestigious engineering colleges in India. It tests not only knowledge but also the ability to apply concepts effectively. Practicing MCQs and objective questions is essential for scoring better, as it helps in familiarizing students with the exam pattern and enhances their problem-solving skills. Engaging with practice questions allows students to identify important questions and strengthen their exam preparation.
What You Will Practise Here
Fundamental concepts of Physics, Chemistry, and Mathematics
Key formulas and their applications in problem-solving
Important definitions and theories relevant to JEE Main
Diagrams and graphical representations for better understanding
Numerical problems and their step-by-step solutions
Previous years' JEE Main questions for real exam experience
Time management strategies while solving MCQs
Exam Relevance
The topics covered in JEE Main are not only significant for the JEE exam but also appear in various CBSE and State Board examinations. Many concepts are shared with the NEET syllabus, making them relevant across multiple competitive exams. Common question patterns include conceptual applications, numerical problems, and theoretical questions that assess a student's understanding of core subjects.
Common Mistakes Students Make
Misinterpreting the question stem, leading to incorrect answers
Neglecting units in numerical problems, which can change the outcome
Overlooking negative marking and not managing time effectively
Relying too heavily on rote memorization instead of understanding concepts
Failing to review and analyze mistakes from practice tests
FAQs
Question: How can I improve my speed in solving JEE Main MCQ questions? Answer: Regular practice with timed quizzes and focusing on shortcuts can significantly enhance your speed.
Question: Are the JEE Main objective questions similar to previous years' papers? Answer: Yes, many questions are based on previous years' patterns, so practicing them can be beneficial.
Question: What is the best way to approach JEE Main practice questions? Answer: Start with understanding the concepts, then attempt practice questions, and finally review your answers to learn from mistakes.
Now is the time to take charge of your preparation! Dive into solving JEE Main MCQs and practice questions to test your understanding and boost your confidence for the exam.
Q. In a potentiometer experiment, if the balance point is found at 4 m with a 6 V battery, what is the voltage across a cell connected to the potentiometer?
A.
2 V
B.
3 V
C.
4 V
D.
6 V
Solution
Using the potential gradient, we can find the voltage across the cell. The potential gradient is 6 V / 10 m = 0.6 V/m. At 4 m, the voltage is 0.6 V/m * 4 m = 2.4 V, which rounds to 2 V.
Q. In a potentiometer experiment, if the balance point is found at 4 m with a known voltage of 12 V, what is the unknown voltage if the balance point for it is at 6 m?
A.
8 V
B.
9 V
C.
18 V
D.
24 V
Solution
Using the formula V1/L1 = V2/L2, we have 12 V / 4 m = V2 / 6 m. Solving gives V2 = 18 V.
Q. In a potentiometer experiment, if the balance point shifts when a load is connected, what does it indicate?
A.
The load has infinite resistance
B.
The load has zero resistance
C.
The load affects the circuit's total resistance
D.
The potentiometer is faulty
Solution
A shift in the balance point indicates that the load connected affects the total resistance in the circuit, altering the potential difference across the potentiometer wire.
Correct Answer:
C
— The load affects the circuit's total resistance
Q. In a potentiometer experiment, if the balancing length is found to be 4m for a cell of unknown EMF, what is the EMF if the potential gradient is 3 V/m?
A.
6 V
B.
8 V
C.
12 V
D.
15 V
Solution
EMF = Potential Gradient × Balancing Length = 3 V/m × 4 m = 12 V.
Q. In a potentiometer experiment, if the balancing length is found to be 50 cm for a cell of emf 1.5V, what is the potential gradient if the total length of the wire is 100 cm?
A.
3 V/m
B.
1.5 V/m
C.
0.5 V/m
D.
2 V/m
Solution
The potential gradient is V/L = 1.5V/0.5m = 3 V/m.
Q. In a potentiometer experiment, if the known voltage is increased, what effect does it have on the balance point?
A.
Balance point moves towards the positive terminal
B.
Balance point moves towards the negative terminal
C.
Balance point remains unchanged
D.
Balance point becomes unstable
Solution
Increasing the known voltage will cause the balance point to move towards the positive terminal, as a higher voltage requires a longer length of wire to achieve balance.
Correct Answer:
A
— Balance point moves towards the positive terminal
Q. In a potentiometer experiment, if the known voltage is increased, what happens to the balance point?
A.
It moves towards the positive terminal.
B.
It moves towards the negative terminal.
C.
It remains unchanged.
D.
It becomes unstable.
Solution
Increasing the known voltage will cause the balance point to move towards the positive terminal, as a higher voltage requires a longer length of wire to balance.
Correct Answer:
A
— It moves towards the positive terminal.
Q. In a potentiometer experiment, if the null point is found at 75cm with a known emf of 1.5V, what is the potential gradient if the total length of the wire is 150cm?
A.
1 V/m
B.
2 V/m
C.
3 V/m
D.
4 V/m
Solution
The potential gradient is V/L = 1.5V/0.75m = 2 V/m.
Q. In a potentiometer experiment, if the wire is made of a material with higher resistivity, what will be the effect on the potential gradient?
A.
It will increase
B.
It will decrease
C.
It will remain the same
D.
It will become zero
Solution
If the wire is made of a material with higher resistivity, the potential gradient will decrease because the resistance increases, leading to a lower current for the same voltage.
Q. In a potentiometer setup, if the known voltage is 6V and the unknown voltage is balanced at 30 cm, what is the potential gradient if the total length of the wire is 120 cm?
A.
2 V/m
B.
1.5 V/m
C.
3 V/m
D.
4 V/m
Solution
The potential gradient is V/L = 6V/0.3m = 20 V/m, but since the total length is 1.2m, the gradient is 5 V/m.
Q. In a potentiometer setup, if the known voltage is increased while keeping the length of the wire constant, what happens to the balance point?
A.
It moves towards the positive terminal
B.
It moves towards the negative terminal
C.
It remains unchanged
D.
It becomes unstable
Solution
If the known voltage is increased, the balance point will move towards the positive terminal, as a higher voltage will require a longer length of wire to achieve balance.
Correct Answer:
A
— It moves towards the positive terminal
Q. In a potentiometer setup, if the known voltage is increased, what happens to the length of the wire required to balance the unknown voltage?
A.
It increases
B.
It decreases
C.
It remains the same
D.
It becomes zero
Solution
If the known voltage is increased, a longer length of wire will be required to balance the unknown voltage, as the potential gradient remains constant.
Q. In a potentiometer setup, if the wire has a resistance of 10 ohms and a current of 0.5 A flows through it, what is the potential drop across the wire?
A.
2.5 V
B.
5 V
C.
10 V
D.
15 V
Solution
The potential drop is calculated using Ohm's law: V = IR = 0.5 A * 10 ohms = 5 V.
Q. In a potentiometer setup, if the wire is made of a material with higher resistivity, what will be the effect on the measurement?
A.
Measurements will be more accurate
B.
Measurements will be less accurate
C.
There will be no effect
D.
It will not work
Solution
Higher resistivity increases the resistance of the wire, which can lead to a larger voltage drop along the wire, potentially affecting the accuracy of the measurements.
Correct Answer:
B
— Measurements will be less accurate
