Tag: physics

Questions Related to physics

Which of the following is not the storage cell?

types of cells electricity physics

  1. Acid cell

  2. NIFE cell

  3. Edison cell

  4. Dry cell

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Correct Option: D
Explanation:

Dry cell being primary cell, cannot be recharged.
Acids cell are used as car batteries.
The nickel-iron battery (Ni-Fe battery)( also called Edison Cell)  is a rechargable battery having nickel(III) oxide-hydroxide positive plates and iron negative plates, with an electrolyte of potassium hydroxide. It is a very robust battery which is tolerant of abuse, (overcharge, overdischarge, and short-circuiting) and can have very long life even if so treated.

First electro chemical cell was designed by?

types of cells electricity physics

  1. Laclanche

  2. Faraday

  3. Galvanic

  4. Some one other than those mentioned above

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Correct Option: D
Explanation:

The battery made by Volta is credited as the first electrochemical cell. It consists of two electrodes: one made of zinc, the other of copper. The electrolyte is either sulfuric acid mixed with water or a form of saltwater brine.

In which of the following cells polarisation is the major defect?

types of cells electricity physics

  1. Voltaic cell

  2. Daniel cell

  3. Leclanche cell

  4. Fuse cell

Show answer
Correct Option: A
Explanation:

The chemical action that occurs in the cell while the current is flowing causes hydrogen bubbles to form on the surface of the anode. This action is called POLARIZATION. Some hydrogen bubbles rise to the surface of the electrolyte and escape into the air, some remain on the surface of the anode. If enough bubbles remain around the anode, the bubbles form a barrier that increases internal resistance. When the internal resistance of the cell increases, the output current is decreased and the voltage of the cell also decreases.

Voltaic cell has a lot of polarization due to ongoing reactions.Daniell cell is an improvement on the voltaic cell using two electrolytes and solves the problem of polarisation.

Which of the following effect of electric current is used in charging a battery of motor car?

types of cells electricity physics

  1. Magnetic

  2. Heating

  3. Chemical

  4. Induction

Show answer
Correct Option: C
Explanation:

The charging of all secondary batteries are based on conversion of electric energy to chemical potential energy with the user of battery charger. The negative terminal of the cell has to be connected to the negative terminal of the voltage source and the positive terminal of the voltage source with the positive terminal of the battery. Further, the voltage output of the source must be higher than that of the battery, but not much higher: the greater the difference between the power source and the battery's voltage capacity, the faster the charging process, but also the greater the risk of overcharging and damaging the battery.

A cell constructed by coupling a standard copper electrode and a standard magnesium electrode has emf of $2.7$ volts. If the standard reduction potential of copper electrode of $+0.34\ V$, that of magnesium electrode is

types of cells electricity physics

  1. $+3.04\ V$

  2. $-3.04\ V$

  3. $+2.36\ V$

  4. $-2.36\ V$

Show answer
Correct Option: D

Assertion: To float; a body must displace liquid whose weight is equal to the actual weight.
Reason: The body will experience no net downward force in that case.

physics floatation experimental verification of archimedes' principle archimedes' principle archimedes' principle and its applications

  1. Both assertion and reason are true and reason is correct explanation of assertion.

  2. Both assertion and reason are true but reason is not the correct explanation of assertion.

  3. Assertion is true but reason is false.

  4. Both assertion and reason are false.

Show answer
Correct Option: A
Explanation:

If the body displaces liquid whose weight is equal to the actual weight of body, the downward force weight will be balanced by the buoyant force and the body won't experience any net downward force in that case.

State whether given statement is True or False
Archimede's principle describes the magnitude of a buoyant force acting on a body that is partly or completely submerged in a fluid.

physics upthrust in fluids, archimedes' principle and floatation experimental verification of archimedes' principle archimedes' principle archimedes' principle and its applications

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Answer is A.

Archimedes' principle indicates that the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially submerged, is equal to the weight of the fluid that the body displaces.
Hence, the given statement is true.

Which one of the following statements is true?

physics upthrust in fluids, archimedes' principle and floatation experimental verification of archimedes' principle archimedes' principle archimedes' principle and its applications

  1. Archimedes' principle can also be applied to gases

  2. The buoyant force depends on the nature of object immersed in the liquid.

  3. Ice floats in water because the density of ice is more than that of water.

  4. Force acting on a unit area is called thrust.

Show answer
Correct Option: A
Explanation:

Answer is A.

The Archimedes principle, states that the buoyant force exerted on a body immersed in a fluid is equal to the weight of the fluid the body displaces. In other words, to calculate the buoyant force on an object we assume that the submersed part of the object is made of water and then calculate the weight of that water.
This principle is valid for any fluid not only liquids (such as water) but also gases (such as air).

 
Hence, only the statement in option A is true.

An iron needle sinks in water as its density is less than 1 $ \displaystyle g/cm^{3} $.

physics upthrust in fluids, archimedes' principle and floatation experimental verification of archimedes' principle archimedes' principle archimedes' principle and its applications

  1. True

  2. False

Show answer
Correct Option: B
Explanation:

Any substance sinks in a liquid of density of S when density of substance is greater than that of liquid i.e.

$\boxed { density\quad of\quad substance\quad >\quad S } $

If a body X floats in liquid Y. The density of body X is greater than liquid Y. True or false

physics upthrust in fluids, archimedes' principle and floatation experimental verification of archimedes' principle archimedes' principle archimedes' principle and its applications

  1. True

  2. False

Show answer
Correct Option: B
Explanation:

For a body to sink in water then density of body should be more than density of water or any fluid i.e. density of body > density of water.