1
JEE Main 2023 (Online) 29th January Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

Surface tension of a soap bubble is $$2.0 \times 10^{-2} \mathrm{Nm}^{-1}$$. Work done to increase the radius of soap bubble from $$3.5 \mathrm{~cm}$$ to $$7 \mathrm{~cm}$$ will be:

Take $$\left[\pi=\frac{22}{7}\right]$$

A
$$18 .48 \times 10^{-4} \mathrm{~J}$$
B
$$5.76 \times 10^{-4} \mathrm{~J}$$
C
$$0.72 \times 10^{-4} \mathrm{~J}$$
D
$$9.24 \times 10^{-4} \mathrm{~J}$$
2
JEE Main 2023 (Online) 29th January Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: If $$d Q$$ and $$d W$$ represent the heat supplied to the system and the work done on the system respectively. Then according to the first law of thermodynamics $$d Q=d U-d W$$.

Reason R: First law of thermodynamics is based on law of conservation of energy.

In the light of the above statements, choose the correct answer from the options given below:

A
Both A and R are correct but R is not the correct explanation of A
B
Both A and R are correct and R is the correct explanation of A
C
A is correct but R is not correct
D
A is not correct but R is correct
3
JEE Main 2023 (Online) 29th January Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

The magnitude of magnetic induction at mid point $$\mathrm{O}$$ due to current arrangement as shown in Fig will be

JEE Main 2023 (Online) 29th January Morning Shift Physics - Magnetic Effect of Current Question 32 English

A
$$\frac{\mu_{0} I}{\pi a}$$
B
$$\frac{\mu_{0} I}{4 \pi a}$$
C
$$\frac{\mu_{0} I}{2 \pi a}$$
D
0
4
JEE Main 2023 (Online) 29th January Morning Shift
MCQ (Single Correct Answer)
+4
-1
Out of Syllabus
Change Language

If a radioactive element having half-life of $$30 \mathrm{~min}$$ is undergoing beta decay, the fraction of radioactive element remains undecayed after $$90 \mathrm{~min}$$. will be

A
$$\frac{1}{16}$$
B
$$\frac{1}{4}$$
C
$$\frac{1}{8}$$
D
$$\frac{1}{2}$$
JEE Main Papers
2023
2021
EXAM MAP
Medical
NEET
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
CBSE
Class 12