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An object 5.0 cm in length is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position of the image, its nature and size.

Radius of curvature (R) = 30 cm f = R/2 = 30/2 = 15 cm u = -20 cm, h= 5 cm. 1/v +1/u = 1/f 1/v = 1/f - 1/u 1/v = 1/15 - 1/-20 v = 8. 57 cm... View Article

Which of the following substances are strongly attracted by magnetic field?a. Ferromagnetic Material b. Diamagnetic Material c. Paramagnetic Material d. None of the above

Answer (a)Ferromagnetic substances are strongly attracted by the magnetic field. Ferromagnetic substances are those substances that when it’s... View Article

An automobile vehicle has a mass of 1500 kg. What must be the force between the vehicle and road if the vehicle is to be stopped with a negative acceleration of 1.7 ms^-2?

Mass of the automobile vehicle (m) = 1500 kg Final velocity (v) = 0 (finally the automobile stops) Acceleration of the automobile (a) = -1.7... View Article

A bomb of mass 16kg at rest, explodes into two pieces of masses 4kg and 12kg. After explosion, the velocity of the 12kg mass is 4m/s. What is the velocity of the 4kg piece?

Given that m1= 4kg m2= 12kg v2= 4m/s Find out The velocity of the 4kg piece Solution The momentum of the system is remaining conserved as... View Article

Which of the following is/are a characteristic of non-living things?a)No capability of growth b)They do not respond to stimuli c)They do not evolve or adapt to their environment d) all of these

The correct answer is option d) all of these What are non-living things? Non-living things are not alive. Things that do not have life are... View Article

Explain how sexual reproduction gives rise to more viable variations than asexual reproduction. How does this affect the evolution of those organisms that reproduce sexually?

In the case of asexual reproduction, only the minimal changes due to inaccuracies in DNA copying pass on to the progeny. Thus, offspring of... View Article

An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the position, size and the nature of the image formed.

Given that The height of object = 5cm Position of object, u = - 25cm The focal length of the lens, f = 10 cm We need to find The position of... View Article

Which of the following hydrocarbon does not undergo addition reaction? C_{2H₆ C₃H₈ C₂H₂ CH₄}

C3H8 and CH4 do not undergo addition reaction. Since these two are unsaturated compounds the addition reaction takes place. An addition... View Article

Which of the following is not a case of chemical equilibrium? i) N2O4 gives 2NO2 ii) NH4Cl(aq) is aqueous solution of NH4Cl(s) iii) N2 + H2 gives 2NH3 iv) PCl5 gives PCl3 + PCl2

NH4Cl(aq) is aqueous solution of NH4Cl(s).... View Article

A battery of 9 V is connected in series with resistors of 0.2 Ohms, 0.3 Ohms, 0.4 Ohms, 0.5Ohms and 12Ohms respectively. How much current would flow through the 12 ohm resistors?

Given A battery of 9 V is connected in series with resistors of 0.2 Ohms, 0.3 Ohms, 0.4 Ohms, 0.5Ohms and 12Ohms respectively Amount of the... View Article

What type of isomerism is present when positive and negative ions of a salt are complex ions and the two isomers differs in the distribution of ligands in the cation and the anion?

Coordination isomerism is present when positive and negative ions of salt are complexions and the two isomers differ in the distribution of... View Article

Alloying is not done for which of the following purpose? a. To enhance the hardness of the metal b. To enhance the tensile strength c. To modify colour d. To raise the melting point

Alloying is not done for option d. To raise the melting point An alloy is a substance formed from a combination of two or more metals. Alloys... View Article

An object of mass 40 kg is raised to a height of 5 m above the ground. What is its potential energy? If the object is allowed to fall, find its kinetic energy when it is half-way down

Mass of the object = 40kg Height = 5m We need to find Potential energy and also its kinetic energy when it is half-way down Potential... View Article

Will the value of Specific latent heat of fusion of a Substance change if the temperature scale is changed from Celsius scale to Fahrenheit scale and from Celsius scale to kelvin scale ?

Fusion involves no change in Temperature as Fusion occurs at constant temperature which is the melting point of the substance. Hence change in... View Article

How do we think the displacement of rod AB will be affected if (i) current in rod AB is increased: (ii) a stronger horse-shoe magnet is used: and (iii) length of the rod AB is increased?

We have learnt that the force acted by a magnet on a current-carrying conductor depends on the following factors Strength of the magnetic... View Article

NaCl molecule is made of which of the following ions? a. Na⁺ and Cl^– b. Na^– and Cl⁺ c.N⁺ and C^– d. N⁺ and C^–

NaCl molecule is made of option a. Na+ and Cl- Sodium chloride is an ionic compound in which the sodium and chloride ions are in the ratio of... View Article

Using divisibility test, determine which of the following numbers are divisibly by 4; by 8: (a) 572 (b) 726352 (c) 5500 (d) 6000 (e) 12159 (f) 14560 (g) 21084 (h) 31795072 (i) 1700 (j) 2150

Let us first know about the divisibility rule If the last two digits of a number are divisible by 4, then that number is a multiple of 4 and is... View Article

Which of the following is significant while diagnosing a disease? a. Attire of the patient b.Language spoken by the patient c.Cultural background of the patient d.Symptoms shown by the patient

Option (d)Symptoms shown by the patient help in diagnosing the disease A disease is a condition that deteriorates the normal functioning of the... View Article

Which one of the following is an example of physical weathering? a. Frost Action b. Weathering due to the reaction between rock and water c. Tree roots fracturing the rock d. None of the above

Frost action is an example of physical weathering. Weathering denotes the process of wearing, breaking up, and fragmentation of the rock that... View Article

Which of the following is the characteristic feature of ferns? a. Ferns have seeds b. Plant body is differentiated into root, stem and leaves c. They have Tuberous roots d. Ferns are gametophytes

Their plant body is differentiated into root, stem and leaves.... View Article