Param Himalaya - परम हिमालय

NCERT Solutions Class 12 Physics Chapter 3 Current Electricity with Video Explanation - Param Himalaya   Question 3.1 : The storage battery of a car has an emf of 12 V. If the internal resistance of the battery is 0.4Ω, what is the maximum current that can be drawn from the battery? Solution :   $$ I_{max} = \frac{E}{r}=\frac{12}{0.4}$$ $$I_{max} = 30 A$$ Question 3.2 : A battery of e.m.f 10V and internal resistance 3Ω is connected to a resistor. If The current in the circuit is 0.5A, what is the resistance of the resistor ? What is the terminal voltage of the battery when the circuit is closed ?  Solution :   $$ I = \frac{E}{R+r}$$ $$R+r = \frac{E}{I}$$ $$R+r=  \frac{10}{.5}=20$$ $$Or\;R = 20 - r = 20 - 3$$ $$R = 17 Ω$$ $$Terminal \ Voltage = IR$$ $$V= IR$$ $$V=0.5×17=8.5Volt$$ Question 3.3 : At room temperature (27.0 °C) the resistance of a heating element is 100 Ω. What is the temperature of the element if the resistance is found to be 117 Ω, given that the...

Scattering of light | Tyndall Effect | Blue colour of Sky | The red colour of the sun at sunrise and sunset  What is Scattering of light?  Scattering of light is the phenomenon in which light rays deviate from their straight path due to the presence of particles or irregularities in the medium they pass through.  The amount of scattering depends on the wavelength of the light and the size of the particles. Shorter wavelengths and higher frequencies scatter more than longer wavelengths and lower frequencies. For example, blue light has a shorter wavelength than red light, so it scatters more in the atmosphere.  What is Tyndall effect?  The Tyndall effect is the phenomenon in which light is scattered by particles in a colloid or in a very fine suspension. A colloid is a mixture in which one substance is dispersed as very small particles in another substance, such as milk, fog, or smoke. A fine suspension is a mixture in which solid particles are suspended in a liq...

Free Download NCERT Complete Book Class 11 Physics Chapter 1 to 14  - Param Himalaya Chapter 1 : Unit and Measurement  Chapter 2 : Motion in a Straight Line Chapter 3 : Motion in a Plane   Chapter 4 : Laws of Motion Chapter 5 : Work , Energy and Power  Chapter 6 : System of Particles and Rotational Motion  Chapter 7 : Gravitation   Chapter 8 : Mechanical Properties of Solids Chapter 9 : Mechanical Properties of Fluids Chapter 10 : Thermal Properties of Matter Chapter 11 : Thermodynamics Chapter 12 : Kinematic Theory   Chapter 13 : Oscillations   Chapter 14 :Waves

NOTES CBSE Class 9 Science Chapter 8 Force and Law of motion - Param Himalaya  Definition of Force :  Force enables us to do any work.  To do anything, either we pull or push the object that produces an acceleration in the object on which it acts Therefore,  pull or push is called force . S.I. unit of force is Newton. Example:  1. To open a door, either we push or pull it.  2. A drawer is pulled to open and pushed to close. Effect of Force :   (i) Force can make a stationary (Rest) body in motion. For example, a football can be set to move by kicking it, i.e., by applying a force. (ii) Force can stop a moving body.  For example, by applying brakes, a running cycle or a running vehicle can be stopped. (iii) Force can change the direction of a moving object.  For example, by applying force, i.e., by moving handle, the direction of a running bicycle can be changed. Similarly by moving steering, the direction of a running vehicle is changed. (iv)...

Momentum is the power of motion of an object. The product of velocity and mass is called the momentum. Momentum is denoted by 'p'. Therefore, Momentum of the object = Mass x Velocity \[p=m\times v\] Where, p= momentum, m = mass of the object and v = velocity of the object Consider the following explanations to understand the momentum: A person get injured in the case of hitting by a moving object, such as stone, pebbles or anything because of momentum of the object. Even a small bullet is able to kill a person when it is fired from a gun because of its momentum due to great velocity. A person get injured severely when hit by a moving vehicle because of momentum of vehicle due to mass and velocity. Since momentum is the product of mass and velocity (p = m x v) of an object. This means momentum is directly proportional to mass and velocity. Momentum increases with increase of either mass or velocity of an object. This means if a lighter and a heavier object is moving with same ve...

Newton studied the ideas of Galileo and gave the three laws of motion. These Laws are known as Newton's laws of motion. Newton's First Law of Motion (Law of Inertia): Any object remains in the state of rest or in uniform motion along a straight line, until it is compelled to change the state by applying external force. Explanation: If any object is in the state of rest, then it will remain in rest until a external force is applied to change its state. Similarly, an object will remain in motion until any external force is applied over it to change its state. This means all objects resist to in changing their state. The state of any object can be changed by applying external forces only. Example : a) A person standing in a bus falls backward when bus starts moving suddenly. This happens because the person and bus both are in rest while bus is not moving, but as the bus starts moving, the legs of the person start moving along with bus but rest portion of his body has the tendency ...

When a particle moves in a straight line with constant acceleration, then the position , time , velocity and acceleration of the particle are represented by equation knowns as kinematic Equations of motion. (i) Velocity attained after time t :  The velocity-time graph for positive constant acceleration of a particle is shown in fiqure . Let u be the initial velocity of the particle at t=0 and v is final velocity of the particle after time t .  Consider two point A and B on the curve corresponding to t=0 and t =t respectively. Draw BD perpendicular on time axis . Also draw AC perpendicular on BD. OA = CD = u ; BC = ( v-u) and OD = t  Now Slope of v - t graph = acceleration (a) \[a = Slope \;of \;v-t \;graph\]\[= tan \Theta = \frac{BC}{AC} = \frac{BC}{OD}\] \[a = \frac{v-u}{t}\] \[or \;v-u=at\] \[v=u+at\] Which is the expression for the velocity atttained by uniformly accelerated particle in time t.  (ii) Distance travelled in time interval t :  Let x o = Position...