TS EAMCET · Physics · Units and Dimensions

If the length of a rod is measured as 830600 mm, then the number of significant figures in the measurement is

A $5$
B $3$
C $6$
D $4$

Verified Solution

Answer & Solution

Correct Answer

(D) $4$

Step-by-step Solution

Detailed explanation

$4$

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

Same subject

Find the equivalent resistance between point $A$ and $B$ in the following circuit. (The resistance of each resistor is $R$ )

TS EAMCET 2020 Medium
A very small hole in an electric furnace is used for heating metals. The hole nearly acts as a black body. The area of the hole is $200 \mathrm{~mm}^2$. To keep a metal at $727^{\circ} \mathrm{C}$, heat energy flowing through this hole per sec, in joules is $\left(\sigma=5.67 \times 10^{-8} \mathrm{Wm}^{-2} \mathrm{~K}^{-4}\right)$

TS EAMCET 2014 Easy
The length of a metal rod is 20 cm and its area of cross-section is $4 \mathrm{~cm}^2$. If one end of the rod is kept at a temperature of $100^{\circ} \mathrm{C}$ and the other end is kept in ice at $0{ }^{\circ} \mathrm{C}$, then the mass of the ice melted in 7 minutes is
(Thermal conductivity of the metal $=90 \mathrm{Wm}^{-1} \mathrm{~K}^{-1}$ and latent heat of fusion of ice $=336 \times 10^3 \mathrm{~J} \mathrm{~kg}^{-1}$ )

TS EAMCET 2025 Medium
A convex lens focusses an object $20 cm$ from it on a screen placed $5 cm$ away from it. A glass plate (refractive index $= \frac{7}{5}$ ) of thickness $1.4 cm$ is inserted between the lens and the screen. What is the distance of the object from the lens, so that its image is again focused on the screen?

TS EAMCET 2022 Hard
The thickness of a uniform rectangular metal plate is 5 mm and the area of each surface is $5 \mathrm{~cm}^2$. In steady state, the temperature difference between the two surfaces of the plate is $14^{\circ} \mathrm{C}$. If the heat flowing through the plate in one second from one surface to the other surface is 42 J , then the thermal conductivity of the metal is

TS EAMCET 2024 Easy
A bomb is dropped on an enemy post on the ground by an aeroplane flying horizontally with a velocity of $60 \mathrm{kmh}^{-1}$ at a height of $490 \mathrm{~m}$. At the time of dropping the bomb, the horizontal distance of the aeroplane from the enemy post so that the bomb hits the target is

TS EAMCET 2023 Medium

Explore more questions on app

From TS EAMCET

Consider a spherical planet which is rotating about its axis such that the speed of a point on its equator is $v$ and the effective acceleration due to gravity on the equator is $\frac{1}{3}$ of its value at the poles. What is the escape velocity for a particle at the pole of this planet.

TS EAMCET 2019 Medium
The limit of resolution of a telescope is $25 \times 10^{-7} \mathrm{rad}$. If the telescope is used to detect light of wavelength $500 \mathrm{~nm}$ coming from a star, the diameter of the objective lens used by telescope is

TS EAMCET 2019 Easy
A particle of mass $m_{1}$ collides with a particle of $m_{2}$ at rest. After the elastic collision, the two particles moves at an angle of $90 °$ with respect to each other. The ratio $\frac{m_{2}}{m_{1}}$ is

TS EAMCET 2020 Hard
When the engine is switched off a vehicle of mass $M$ is moving on a rough horizontal road with momentum $p$. If the coefficient of friction between the road and tyres of the vehicle is $\mu_k$, the distance travelled by the vehicle before it comes to rest is

TS EAMCET 2012 Easy
An ideal gas in a cylinder is compressed adiabatically to one-third of its original volume. A work of $45 \mathrm{~J}$ is done on the gas by the process. The change in internal energy of the gas and the heat flowed into the gas, respectively are

TS EAMCET 2018 Easy
Two concentric coils of 10 turns each are placed in the same plane. Their radii are $20 \mathrm{~cm}$ and $40 \mathrm{~cm}$ and carry 0.2 and $0.3 \mathrm{~A}$. current respectively in opposite directions. The magnetic induction (in T) at the centre is

TS EAMCET 2008 Medium

Explore more questions on app