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X Class 10 Physics 📖Electricity in simplify way by JSunil sir 🔭  I'd be happy to simplify the chapter on Electricity for tenth standard🤔 students: 🪄In JSunil Sir 🪄way ⤵️➡️➡️➡️➡️⬆️⬆️↩️⤵️ #Electricity is like magic ✨ that #powers our world. It's the flow of tiny particles called electrons through wires and circuits.  👉Let's break it down into simple bits: 1. What is Electricity? Electricity💡♉ is the movement of tiny particles called electrons . Imagine them like little energy carriers that flow through materials, making things work. 2. Circuits and Pathways Think of circuits like a path for the electrons to travel. A circuit needs three things: a power🪫 source (like a battery), a pathway (wires), and something to use the electricity (a bulb or device). 3. Current ⚡and Voltage🔋 Current is the flow of electrons in a circuit, and voltage is the "push" that makes them move. It's like water flowing in a river (current) because of the slope (volta...

Class 10 physics chapter source of Energy for Class 10 science Q.1. Choose the incorrect statement Source of Energy (a) It is expected to harness wind power to minimum in open space. (b) The potential energy content of wind blowing at high altitudes is the source of wind power. (c) Wind hitting at the blades of a windmill causes them to rotate. The rotation thus achieved can be utilized further (d) One possible method of utilizing the energy of rotational motion of the blades of a windmill is to run the turbine of an electric generator. Ans (b) Q.2. Acid rain happens because: (a) sun leads to heating of upper layer of atmosphere. (b) burning of fossil fuels release oxides of carbon, nitrogen and sulphur in the atmosphere. (c) electrical charges are produced due to friction amongst clouds. (d) earth atmosphere contains acids. Ans . (b) Q.3. In a hydro power plant (a)potential energy possessed by stored water is converted into electricity. (b) kinetic energy possessed by stored water is...

X Atmospheric Refraction and Scattering and Tyndal effect of light related topic-based question answer for CBSE Board Examination CBSE NCERT Physics Class 8 and class 10 chapter light The change in path of light as it passes through the atmosphere is known as atmospheric refraction. Effects are Blue colour of sky, rainbow in the sky, difference in colours of the Sun observed during sunrise/sunset and noon, sun appears reddish whereas at noon the sun appears white. 1. What is the difference in colours of the Sun observed during sunrise/sunset and noon? Give explanation for each. Ans: During sunrise and sunset the sun appears reddish whereas at noon the sun appears white. At sunrise and sunset, the light coming from the sun has to travel a longer distance through the atmosphere to reach us. Therefore, the blue and green components of white light are gets scattered away Hence, during sunrise and sunset the sun appears reddish. When the sun is overhead at noon, then the light coming f...

Class 10 our environment board solved Questions 2016 1. What is the function of ozone in upper atmosphere? Ans: It shields the surface of the earth from ultraviolet rays from the Sun. 2. Why should biodegradable and non biodegradable waste be discarded in two separate dustbins? Ans: So that the time and energy required in segregation may be saved and waste may be disposed off quickly 3. The following organisms form a food chain. Which of these will have the highest concentration of non-biodegradable chemicals ? Name the phenomenon associated with it. Insects, Hawk, Grass, Snake, Frog. Ans: Hawk ; Biomagnifications 4.. Write the full name of the group of compounds mainly responsible for the depletion of ozone layer. Ans: Chloroflurocarbons 5. List two examples of natural ecosystem. Ans: Forests ,Ponds,Lakes 6. Differentiate between biodegradable and non-biodegradable substances with the help of one example each. List two changes in habit that people must adopt to dispose non-biodegrad...

HOTS Questions with Answer:   Magnetic Effects of Electric Currents Q1.On what factors does the magnetic field intensity at the centre of the circular coil carrying current  depend ? Answer: The magnetic field intensity at the centre of the circular coil is directly proportional to current and inversely proportional to radius of the coil. So, in both the cases ,that is, twice the current as well as half in radius, the magnetic field intensity gets doubled. The magnitude of the magnetic field (B) at the of the coil is: (i). directly proportional to the current (I) flowing it.       i.e.   B α I                           ① (ii). Inversely proportional to the radius (r) of the coil     i.e.  B α  1/r           ...

1. The current passing through a room heater has been halved. What will happen to the heat produced by it? 2. An electric iron of resistance 20 ohm draws a current of 5 amperes. Calculate the heat produced in 30 seconds. 3. An electric heater of resistance 8 ohm takes a current of 15 A from the mains supply line. Calculate the rate at which heat is developed in the heater. 4. A resistance of 40 ohms and one of 60 ohms are arranged in series across 220 volt supply. Find the heat in joules produced by this combination in half a minute. 5. A resistance of 25 ohm is connected to a 12 V battery. Calculate the heat energy in joules generated per minute. 6. 100 joules of heat is produced per second in a 4 ohm resistor. What is the potential difference across the resistor? 7. An electric iron is connected to the mains power supply of 220 V. When the electric iron is adjusted at minimum heating’ it consumes a power of 360 W but at ‘maximum heating’ it takes a power of 840 W. Ca...

Atmospheric Refraction related question for CBSE Board CBSE NCERT Physics Class 8 and class 10 chapter light 1. A student sitting at the back of the classroom cannot read clearly the letters written on the blackboard. What advice will a doctor give to her? Ans: The student is suffering from myopia (near sightedness). Doctor advises her to use a concave lens of appropriate power to correct this defect.   2. How are we able to see nearby and also the distant objects clearly? Ans: Human eye is able to see nearby and distant objects clearly by changing the focal length of the eye lens using its power of accommodation. 3. A person needs a lens of power –4.5 D for correction of her vision. (a) What kind of defect in vision is she suffering from? (b) What is the focal length of the corrective lens? (c) What is the nature of the corrective lens? Ans: (a) Negative sign of power of lens indicates that focal length is negative that is only possible in concave lens that is used f...

Q. 1. A concave mirror of focal length 20cm is placed 50 cm from a wall. How far from the wall an object be placed to form its real image on the wall?  Solution: V= -50 cm F= -20cm From mirror formula 1/u = 1/f – 1/v = -1/20+ 1/50 = - 3/100  U = - 33.3 cm Therefore, the distance of the object from the wall x =  50 – u X = 50 – 33.3 = 16.7 cm. Q.2. An object is placed at a distance of 40cm from a concave mirror of focal length 15cm. If the object is displaced through a distance of 20 cm towards the mirror, By how much distance is the image displaced? Answer: Here f = - 15 cm, u = - 40 cm Now 1/f = 1/u + 1/v Then 1/v = 1/f – 1/u Or V= uf/u-f =( - 40 x -15)/25 = -24 cm Then object is displaced towards the mirror let u1 be the distance object from the Mirror in its new position. Then u1 = -(40-20) = -20cm If the image is formed at a distance u1 from the mirror then v1 = u1f/u1-f = -20X-15/-20+15 = -60 cm. = - 20 x-15/-20+15 = -60 ...