A wire of resistance R is cut into 8 equal pieces. From these pieces two equivalent resistances are made by adding four of these together in parallel. - Physics MCQ Physics | ExamTest.live

hardMCQPhysicsPhysics

35 attempts6% success rate1 mark

A wire of resistance R is cut into 8 equal pieces. From these pieces two equivalent resistances are made by adding four of these together in parallel. Then these two sets are added in series. The net effective resistance of the combination is:

A $\frac{R}{64}$
B $\frac{R}{32}$
C $\frac{R}{16}$
D $\frac{R}{8}$

Solution & Step-by-step Explanation

1. Resistance of individual piece: Since the wire is cut into 8 equal pieces, the resistance of each piece is r = \frac{R}{8} .2. Parallel Combination: Four pieces are connected in parallel. R_{p a r a ll e l} = \frac{r}{4} = \frac{R /8}{4} = \frac{R}{32} .3. Series Combination: Two such parallel sets are added in series. R_{n e t} = R_{p a r a ll e l} + R_{p a r a ll e l} = \frac{R}{32} + \frac{R}{32} = \frac{2 R}{32} = \frac{R}{16} .

Practice this question

Try it yourself before checking the explanation above.

A wire of resistance R is cut into 8 equal pieces. From these pieces two equivalent resistances are made by adding four of these together in parallel. Then these two sets are added in series. The net effective resistance of the combination is:

\frac{R}{64}

\frac{R}{32}

\frac{R}{16}

\frac{R}{8}

Share This Question

Current Electricity Resistance Combination of Resistors

Related Questions

mediumMCQ

Consider a water tank as shown in the figure. It has one wall at x = L and is very wide in the z direction. When filled with a liquid of surface tension S and density ρ , the liquid surface makes an angle θ_0 ( θ_0 1 ) with the x -axis at x = L . If y(x) is the height of the surface, then the equation for y(x) is:(Take θ(x) ≈ θ(x) ≈ θ(x) = dy/dx and g as acceleration due to gravity) ![image](https://pub-7faa453bd1ec4bf0a04cc031c6f058de.r2.dev/images/e48999a7-2b29-4d5c-be16-ae2fd5fbcea5.png)

mediumMCQ

A microscope has an objective of focal length 2 cm , eyepiece of focal length 4 cm and the tube length of 40 cm . If the distance of distinct vision of eye is 25 cm , the magnification in the microscope is:

mediumMCQ

An electron (mass 9 × 10^-31 kg and charge 1.6 × 10^-19 C ) moving with speed c/100 ( c = speed of light) is injected into a magnetic field B of magnitude 9 × 10^-4 T perpendicular to its direction of motion. We wish to apply a uniform electric field E together with the magnetic field so that the electron does not deflect from its path. Then (speed of light c = 3 × 10^8 ms^-1 ):

mediumMCQ

There are two inclined surfaces of equal length ( L ) and same angle of inclination 45^ with the horizontal. One of them is rough and the other is perfectly smooth. A given body takes 2 times as much time to slide down on rough surface than on the smooth surface. The coefficient of kinetic friction ( μ_k ) between the object and the rough surface is close to:

mediumMCQ

The kinetic energies of two similar cars A and B are 100 J and 225 J respectively. On applying breaks, car A stops after 1000 m and car B stops after 1500 m . If F_A and F_B are the forces applied by the breaks on cars A and B, respectively, then the ratio F_A/F_B is:

hardMCQ

A model for quantized motion of an electron in a uniform magnetic field B states that the flux passing through the orbit of the electron is n(h/e) where n is an integer, h is Planck's constant and e is the magnitude of electron's charge. According to the model, the magnetic moment of an electron in its lowest energy state will be ( m is the mass of the electron):

Ready for a Full Test?

Practice with timed mock tests and track your performance across Physics.

Browse Tests Leaderboard

A wire of resistance $R$ is cut into $8$ equal pieces. From these pieces two equivalent resistances are made by adding four of these together in parallel. Then these two sets are added in series. The net effective resistance of the combination is:

Solution & Step-by-step Explanation

Practice this question

Share This Question

Related Questions

Ready for a Full Test?

Discussion