1
WB JEE 2023
MCQ (Single Correct Answer)
+1
-0.25

In an experiment, the length of an object is measured to be 6.50 cm. This measured value can be written as 0.0650 m. The number of significant figures on 0.0650 m is

A
3
B
4
C
2
D
5
2
WB JEE 2023
MCQ (Single Correct Answer)
+2
-0.5

A modified gravitational potential is given by $$\mathrm{V}=-\frac{\mathrm{GM}}{\mathrm{r}}+\frac{\mathrm{A}}{\mathrm{r}^{2}}$$. If the constant A is expressed in terms of gravitational constant (G), mass (M) and velocity of light (c), then from dimensional analysis, A is,

A
$$\frac{G^{2} M^{2}}{c^{2}}$$
B
$$\frac{\mathrm{GM}}{\mathrm{c}^{2}}$$
C
$$\frac{1}{c^{2}}$$
D
Dimensionless
3
WB JEE 2022
MCQ (Single Correct Answer)
+1
-0.25

Given : The percentage error in the measurements of A, B, C and D are respectively, 4%, 2%, 3% and 1%. The relative error in $$Z = {{{A^4}{B^{{1 \over 3}}}} \over {C{D^{{3 \over 2}}}}}$$ is

A
$${{127} \over 2}\% $$
B
$${{127} \over 5}\% $$
C
$${{127} \over 6}\% $$
D
$${{127} \over 7}\% $$
4
WB JEE 2022
MCQ (Single Correct Answer)
+1
-0.25

The Entropy (S) of a black hole can be written as $$S = \beta {k_B}A$$, where kB is the Boltzmann constant and A is the area of the black hole. The $$\beta$$ has dimension of

A
L2
B
ML2L$$-$$1
C
L$$-$$2
D
dimensionless
WB JEE Subjects