What will be the value of T if A copper ball of mass 100 gm is at a temperature T. It is dropped in a copper calorimeter of mass 100 gm,filled with 170 gm of water at room temperature. Subsequently, the temperature of the system is found to be 750C. T is given by: (Given : room temperature = 300C, specific heat of copper = 0.1 cal/gm0C)?

Anshul Kumar Singh Physics 26 Aug, 2017 377 views

What will be the variance of the number of green balls drawn if A box contains 15 green and 10 yellow balls. If 10 balls are randomly drawn, one-by-one, with replacement?

Rahul Kumar Maths 22 Aug, 2017 86 views

A compound ‘X’ reacts with a compound ‘Y’, to produce a colourless and odourless gas. The gas turns lime water milky. When ‘X’ reacts with methanol in the presences of concentrated H2SO4, a sweet smelling substance is produced. The molecular formula of the compound ‘X’

Anshul Kumar Singh Chemistry 09 Aug, 2017 484 views

What is cuboid? What will be the real time examples of the cuboid.

Arpita Singh Maths 05 Aug, 2017 144 views

The following observations were taken for determining surface tension T of water by capillary method: diameter of capillary, D = 1.25 *10^-2m rise of water, h = 1.45 *10^2m Using g = 9.80 m/s2 and the simplified relation T = (rhg*10^)/2 N/ m, the possible error in surface tension is closest to?

Rahul Kumar Physics 04 Aug, 2017 213 views

What will be the variance of the number of green balls drawn is if A box contains 15 green and 10 yellow balls. If 10 balls are randomly drawn, one by one, with replacement?

Rahul Kumar Maths 03 Aug, 2017 105 views

What will be maximum area (in sq. m) of the flower-bed if Twenty meters of wire is available for fencing off a flower-bed in the form of a circular sector?

Rahul Kumar Maths 02 Aug, 2017 75 views

A rocket is launched normal to the surface of earth, away from the Sun, along the line joining the Sun and the Earth. The Sun is 3 *10^5 times heavier than the Earth and is at a distance 2.5 *10^4 times larger than the radius of the Earth. The escape velocity from Earth’s gravitational field is ve = 11.2 km /s The minimum initial (vs) required for the rocket to be able to leave the Sun-earth system is closest to(Ignore the rotation and revolution of the Earth and the presence of any other planet).

Rahul Kumar Physics 30 Jul, 2017 305 views

An electron in a hydrogen atom undergoes a transition from an orbit with quantum numebr ni to another with quantum number nf. Vi and Vf are respectively the initial and final potential energies of the electon. If vi/ vf =6.25, Then what is smallest possible nf is

Preeti Rai Chemistry 29 Jul, 2017 433 views

The sides of a right angled triangle are in arithmetic progression. If the triangle has area 24, then what is the length of its smallest side ?

Rahul Kumar Maths 29 Jul, 2017 1067 views

If a chord, which is not a tangent, of the parabola y2 = 16x has the equation 2x + y = p, and midpoint (h, k), then what is(are) possible value(s) of p, h and k ?

Anshul Kumar Singh Maths 29 Jul, 2017 1079 views

A crystalline solid of a pure substance has a face-centred cubic structure with a cell edge of 400 pm. If the density of the substance in the crystal is 8 g cm-3, then the number of atoms present in 256 g of the crystal is N × 1024. The value of N?

Rahul Kumar Chemistry 28 Jul, 2017 989 views

Why colour of the X2 molecules of group 17 elements changes gradually from yellow to violet down the group?

Preeti Rai Chemistry 28 Jul, 2017 105 views

How many unpaired electrons are present in Co3+ ion?

Ritesh Rai Chemistry 27 Jul, 2017 2166 views

How many groups are occupied by p-block elements in long form of periodic table?

Ritesh Rai Chemistry 26 Jul, 2017 288 views

What is the power of accommodation of the eye?

Rahul Kumar Physics 25 Jul, 2017 66 views

A myopic person uses specs of power –0.5 D. What is the distance (in meter) of the far point of his eye?

Ritesh Rai Physics 25 Jul, 2017 1447 views

Two balls are dropped to the ground from different heights. One ball is dropped 2s after the other but they both strike the ground at the same time. If the first ball takes 5s to reach the ground, then the difference in initial heights is (g = 10 ms–2) 40

Preeti Rai Physics 23 Jul, 2017 4338 views

16. A train covers a distance of 90km at a uniform speed. Had the speed been 15km/hr more, it would have taken half an hour / hr for the journey. What will be the original Speed of the train.

Anshul Kumar Singh Physics 23 Jul, 2017 87 views

15. In a two digit number, the sum of the digits is 13. If the number is subtracted from the one obtained by inter changing the result is 45. Find the number.

Anshul Kumar Singh Maths 22 Jul, 2017 106 views

What will be current through electric iron if an electric iron rated as 800W, 200V operating at the voltage of 100V?

Anshul Kumar Singh Physics 21 Jul, 2017 99 views

What will be energy of an alfa particle when it is accelerated by a potential difference of 3V?

Anshul Kumar Singh Physics 16 Jul, 2017 63 views

Number of electrons to be put on a spherical conductor of radius 0.1 m to produce an electric field of 0.036N/C just above its surface is

Anshul Kumar Singh Physics 15 Jul, 2017 426 views

An Athletic completes one round of a circular track of radius 2.5 m in 12 sec. What will be the magnitude of displacement (in meter) at the end of 54 sec.

Anshul Kumar Singh Physics 15 Jul, 2017 201 views

What will be the relative rates of diffusion between CH4 and SO2? (Mol. mass of SO2 = 64 & CH4 = 16)

Anshul Kumar Singh Chemistry 12 Jul, 2017 271 views

Find the volume of a pyramid whose base is a square with side lengths of 10 m and height 9 m.

Anshul Kumar Singh Maths 10 Jul, 2017 63 views

How many edges faces and vertices are on a cone?

Ashish Maurya Maths 09 Jul, 2017 91 views

What type of pyramid has four faces?

Ashish Maurya Maths 09 Jul, 2017 84 views

What is the edge of a cube?

Ashish Maurya Maths 09 Jul, 2017 64 views

What is a square based pyramid?

Ashish Maurya Maths 09 Jul, 2017 74 views

How many vertices are in a pyramid?

Ashish Maurya Maths 09 Jul, 2017 69 views

What is the number of vertices in a pyramid with 10 faces?

Ashish Maurya Maths 09 Jul, 2017 141 views

What is the rate of acceleration of gravity?

Preeti Rai Physics 07 Jul, 2017 70 views

Mr. Sharma and Mr. Arora are family friends and they decided to go for a trip with family . For the trio they reserved their rail tickets . Mr. Arora has not taken a half ticket for his child who is 6 years old where as Mr, Sharma has taken half tickets for his two children who are 6 year and 8.5 year.A railway half ticket costs half of the full fare but the reservation charges are the same as on a FULL TICKET. MR AND MRS ARORA PAID 1700,WHILE MR AND MRS SHARMA PAID 2700. Find the full share of one ticket and reservation charges per ticket.

Ashish Maurya Maths 07 Jul, 2017 1471 views

Can the number n ^6,n being a natural number ,end with the digit 5? Give reasons.

Ashish Maurya Maths 07 Jul, 2017 294 views

A man has certain note of denomination 20 and 5 which amount to 380 . If the number of notes of each kind are interchanged,they amount to 60 less than before . Find the number of notes of each denomination.

Ashish Maurya Maths 07 Jul, 2017 459 views

Explain with a suitable diagram

Preeti Rai Biology 05 Jul, 2017 74 views

Explain why sodium is more reactive than lithium.

Preeti Rai Chemistry 05 Jul, 2017 75 views

What is dispersion?

Abhay Rai Physics 05 Jul, 2017 64 views

What kind of lens is used in spectacles of a person suffering from myopia?

Abhay Rai Physics 05 Jul, 2017 92 views

What is the matrix and what is the use of it? What are the types and how it works?

Niti Gupta Maths 05 Jul, 2017 68 views

What is hysteresis loss? Where does the loss actually occur?

Mitali Rajpoot Physics 05 Jul, 2017 69 views

What is Atom? What is Mass? What is difference between both?

Arun Sharma Chemistry 05 Jul, 2017 61 views

What is th formula of sodium sesquicarbonate, which is used for wool washing

Ritesh Rai Chemistry 05 Jul, 2017 207 views

What is Distance and displacement calculation? What is the difference between both of you.

Arpita Singh Maths 04 Jul, 2017 78 views

Niti Gupta English 03 Jul, 2017 63 views

What is the meaning of microvascular niche? What does niche refer to in biology?

Kirti Gulati Biology 03 Jul, 2017 73 views

What is ascent of sap?

Preeti Rai Biology 03 Jul, 2017 71 views

Name the largest blood vessel in the human body

Preeti Rai Biology 03 Jul, 2017 81 views