NCERT Syllabus for Class 9 Hindi 2025-26 - Sanchayan, Kshitij, Sparsh, Kritika

A block of mass 0.50 kg is moving with a speed of 2.00 ms^-1 on a smooth surface. It strikes another mass of 1.00 kg and then they move together as a single body. The energy loss during the collision is

A person trying to lose weight by burning fat lifts a mass of 10 kg upto a height of 1 m 1000 times.  Assume that the potential energy lost each time he lowers the mass is dissipated.  How much fat will he use up considering the work done only when the weight is lifted up ?  Fat supplies 3.8×10⁷ J of energy per kg which is converted to mechanical energy with a 20% efficiency rate.  Take g = 9.8 ms⁻² :

An athlete in the olympic games covers a distance of 100 m in 10 s. His kinetic energy can be estimated to be in the range

A particle is projected at 60⁰   to the horizontal with a kinetic energy . The kinetic energy at the highest point

In the reaction,

How many moles of magnesium phosphate, will contain 0.25 mole of oxygen atoms?

If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will

With increase of temperature, which of these changes?

Number of atoms in 558.5 gram Fe (at. wt.of Fe = 55.85 g mol^-1) is

A pulley of radius 2 m is rotated about its axis by a force F = (20t - 5t²) newton (where t is measured in seconds) applied tangentially. If the moment of inertia of the pulley about its axis of rotation is 10 kg m² , the number of rotations made by the pulley before its direction of motion if reversed, is