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Ohm’s law states that the voltage or potential difference between two points is directly proportional to the current or electricity passing through the resistance, and inversely proportional to the resistance of the circuit. The formula for Ohm’s law isV=I/R. This relationship between current, voltage, and relationship was discovered by German scientist Georg Simon Ohm. Let us learn more about Ohms Law, Resistance, and its applications.

Ohm’s Law Definition

Most basic components of electricity are voltage, current, and resistance. Ohm’s law shows a simple relation between these three quantities.Ohm’s lawstates that the current through a conductor between two points is directlyproportional to the voltage across the two points.



Ohm’s Law Formula

Voltage= Current× ResistanceV= I×RV= voltage, I= current and R= resistance

The SI unit of resistance isohmsand is denoted byΩ

This law is one of the most basic laws of electricity. It helps to calculate the power, efficiency, current, voltage, and resistance of an element of an electrical circuit.

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Applications of Ohm’s Law

Ohm’s law helps us in determining either voltage, current or impedance or resistance of a linear electric circuit when the other two quantities are known to us. It also makes power calculation simpler.

the shape of the graph obtained by plotting current on the vertical axis and voltage on the horizontal axis is a straight line passing through the origin as shown in the following graph.Note: Slopeof the Graph with current on the vertical axis and voltage on the horizontal axis represents theResistanceof the material of the conductor.

Anelectric generatorworks on theprincipleof Faraday's law of electromagnetic induction. Faraday's law of electromagnetic induction states that “whenever a current carrying conductor are placed in the magnetic field, then a flux is induces in the circuit due to which a current start to flow in the rotor also.

So smart!!

SONAR TECHNOLOGY IS USED TO DISCOVER OBJECT IN DEEP INSIDE SERA

C is the right answer

James Cook discovered Antartica

The first confirmed sighting of mainlandAntarctica, on 27 January 1820, is attributed to the Russian expedition led by Fabian Gottlieb von Bellingshausen and Mikhail Lazarev,discoveringan ice shelf at Princess Martha Coast that later became known as the Fimbul Ice Shelf.

Fabian Gottlieb von Bellingshausen

discovered Antarcticaplz like my answer

James Cook discovered Antarctica

mikhail lazarev discovered antarctica

Downward acceleration is g sin∅-∪gcos∅Time taken is for incline distance=1/2(gsin∅-∪gcos∅)t^2since angle is 45° and ratio of time is x,(g/√2-∪g/√2)/(g/√2)=1/x^2∪=1-(1/x^2)

Let the dimensions of A be l, b, h soz volume will be lbh

the dimensions of B be 3l/2 , 3b/2 , 3h/2 so, volume will be v = (3/2)³× lbh

now ratio of soap B/A = (3/2)³lbh/lbh = (3/2)³ = 3.375

option 3

Man-made satellites don't fall out of space for the same reason that the moon (a big satellite) doesn't crash into the earth, or that the Earth doesn't crash into the Sun. The reason is actually described through Newton's laws of motion.

A moving object will continue to move in a straight line at the same speed unless a force acts on it. For an object to move in a circle, a force has to act on it all the time.This force is called thecentripetal force. It acts towards the centre of the circle. Gravity is the centripetal force that keeps planets moving around the Sun, and satellites moving around planets.

Gravity is the universal force of attraction between masses. It provides the centripetal force needed tokeep a satellite in orbitaround a planet, or a planet inorbitaround a star such as the Sun.

because there is gravity that holds the satellite

When he moves down

mg-nmg=ma

a=g(1-n)

Acyclistwhile going round acurveon a horizontal track has to bend himself a little from his vertical position in order to avoided overturning. When he bends himself inward, a component of the reaction of road provides him the necessary centripetal force for circular motion.

2. In order to find the angle through which a cyclist has to bend himself to take a safe turn, let us assume thatm= combined mass of cycle and cyclistv= uniform speed with which the cyclist takes the turnr=radius of circular trackAnd θ = angle through which the cyclist bend from vertical3. Suppose G represents the centre of gravity of the system (following figure shows). If force of friction between the cycle and the road is not taken into account, then following two forces act on the system at the point G.a) Weight mg of the system acting vertically downloads through the centre of the gravity of the system.b) Reaction R exerted by the road on the system acting along GR at the angle θ with the vertical.

4. The reaction R can be resolved into two rectangular components.a) R cosθ, acting vertically upwards,b) R sinθ, acting horizontally i.e, along the radius and towards the centre of the circular track horizontal component R sin θ provides the necessary centripetal force. Hence:R cos θ=mg………………(1)Rsin θ = mv2/r ………..(2)Dividing eq.(2) by eq. (1), we haveR sin θ/R cos θ=(mv2/r)/mg or tan θ v2/rgOrθ = tan-1(v2/rg)

a cyclist inclines himself the vertical while moving round a circular path to provide necessary centripetal force. On doing this, the normal reaction of the road makes an angle with the vertical and the horizontal component of the reaction provides the necessary centripetal force to move the cycle in the circular path.i.e. Centripetal force (Fc) = Rsinθ

from work energy theoram

(Work done)P.E -Wf = change in K.E

=> 300*6 - Wf = 1/2*(30)*(8²-1.2²) = 15*(62.56)

=> Wf = 1800 -938.4=> wf = 861Nm

option 1

Resistance , R = 26Ω Length of wire , L = 1m diameter of circular part of wire ,d = 0.3mm = 0.3 × 10⁻³m so, base area of wire , A = πr² = πd²/4 [ ∵d = 2r] = 3.14 × (0.3 × 10⁻³)²/4m²= 3.14 × 9 × 10⁻⁸/4 m² = 28.26/4 × 10⁻⁸ m² = 7.06 × 10⁻⁸ m²

Now, use formula, R = ρL/A Here, R is the resistance, ρ is the resistivity , L is the length of wire and A is the base area of it .So , ρ = RA/L = 26Ω × 7.06 × 10⁻⁸m²/1mρ = 1.8356 × 10⁻⁶ Ωm

Hence, resistivity is 1.8356 × 10⁻⁶ Ωm at 20°C

ADSL

Resistance , R = 26Ω Length of wire , L = 1m diameter of circular part of wire ,d = 0.3mm = 0.3 × 10⁻³m so, base area of wire , A = πr² = πd²/4 [ ∵d = 2r] = 3.14 × (0.3 × 10⁻³)²/4m²= 3.14 × 9 × 10⁻⁸/4 m² = 28.26/4 × 10⁻⁸ m² = 7.06 × 10⁻⁸ m²

Now, use formula, R = ρL/A Here, R is the resistance, ρ is the resistivity , L is the length of wire and A is the base area of it .So , ρ = RA/L = 26Ω × 7.06 × 10⁻⁸m²/1mρ = 1.8356 × 10⁻⁶ Ωm

Hence, resistivity is 1.8356 × 10⁻⁶ Ωm at 20°C

thanks

her

Formula : R = þ × length/Cross section area

We have , Resistance, Length and Area has been given.

↪ Resistance = 100 Ω,

↪ Cross section area = 3 × 10⁻⁷ m²

↪ Length = 5 m

↪ 100 = þ × 5 ÷ ( 3 × 10⁻⁷ )

↪ 100( 3 × 10⁻⁷ ) ÷ 5 = þ

↪ 20 × 3 × 10⁻⁷ = þ

↪ 6 × 10⁻⁷⁺¹ = þ

↪ 6 × 10⁻⁶ Ω = þ

Therefore, Required Resistivity of resistance of metal is 6 × 10⁻⁶ Ω meters .

Alexander Graham Bell discovered the telephone

Graham Bell is the right answer.

the answer is graham bell

Graham bell is the right answer

Graham bell discovered the telephone

Graham bell discovered the telephone

Alexander Graham Bell & Antonio Meucci discovered telephone

Length can be measured by a linear scale rod. The scale is kept with any mark matching the starting edge of object. We will get a mark at the ending point of object. Final mark-Initial mark= the length of object .

Mass can be measured by a common balance where weights are placed in one pan and the required object in another and when the support comes to an equilibrium, the Mass is known.

Time can be measured by a stop watch. The button needs to be pressed before the starting if event and again as the event ends. For more accurate measurements, instruments like chronometer can be used.

No, it is not possible to havethunderwithout lightning.Thunderis a direct result of lightning. However, it is possible that you might seelightningand not hear thethunderbecause it was too far away. Sometimes this is called “heatlightning” because it occurs most often in the summer.

No, it is not possible to have thunder without lightning. Thunder is a direct result of lightning. However, it is possible that you might see lightning and not hear the thunder because it was too far away. Sometimes this is called “heat lightning” because it occurs most often in the summer.

Thunderstorms always have lightning (thunder is caused by lightning, and you can't have a thunderstorm without thunder), but you can have lightning without a thunderstorm. Lightning can also be seen in volcanic eruptions, extremely intense forest fires, surface nuclear detonations, and in heavy snowstorms.

No, it is not possible to havethunderwithout lightning.Thunderis a direct result of lightning. However, it is possible that you might seelightningand not hear thethunder because it was too far away. Sometimes this is called “heatlightning” because it occurs most often in the summer.

The relationship between magnification and focal length for different optical instruments or devices is different.

For a single thin lens, magnification, m, can be written as:

m = f/(f-u)

Here f is the focal length of the thin lens and u is the distance between the lens and object.

(2) is correct option

In generators thefunction of brushesis to make contact with the rotating rings and through them to supply current to the coil. Inelectric motorthebrushesare called commutators and thefunctionof commutator in anelectric motoris to reverse the direction of current through the coil periodically

35 is correct answer.

wrong small mistake please check

right

Option c b ok by this is right answer

wgvfhjjjdsatikkcdhkjfcchj

bahi iska answer hai Sayeed hoga 36 sec

The correct answer is 35 seconds

Option c is the right answer

option C is the correc answer

THE DISPLACEMENT :-1000 DISTANCE=1250MTRS

Displacement :- 4000Distance:-4000

Displacement :- 4000Distance:-4000

the displacement=100 distance=1250 Miters

is the correct answer

the displacement=100metre

length of the rectangular field = 500m

width of rectangular field of 300m

length of diagonal = √(500^2 + 300^2) = √(250000 + 90000) = √(340000) = 583.096 m

distance travelled by him = 500 + 300 = 800 m

displacement of him = 583.095 m (ANS)

physics ka tha ye que distance and displacement se correct answer

thanks for your help

a comet leaves behind a glazed white trail but meteor doesn't do so.

D) Polaroids are used.

thank u so much

power in A.C = Vrms*Irms*cos∅ = 100/√2*0.1/√2*cos(π/3) = 10/4 = 2.5w

option C

2.The SI unit of power of a lens is diopter.(D)3. The following law is snell's law of refraction or reflection.

1)Newton's Second law of motion :- The rate of change of momentum is directly proportional to the force applied on the system.Force applied is directly proportional to the product of mass and acceleration .Let be the initial and final momentums respectively.According to newton's second law :-pf - pi / t ∝ FWe know that,Momentum ( P) = mv .Let v be the final and u be the initial velocity .Now,mv - mu / t ∝ FF ∝ m ( v-u) /tF ∝ ma.F = kma.Here, K is the proportionality constant. It's value is 1 .Units of Force are given by the units of mass and acceleration. Units of force is Kgm/s² .In accordance to honour the contributions of Newton, 1 kgm/s² is termed as 1 Newton.

Momentum = mass * velocity.

Total momentum of a system is always conserved. During a collision, momentum lost by one body is gained by another body. During a collision , assume F1 and F 2 be the forces acting on the two bodies. Assuming that only one collision takes place and assuming it to be an isolated system , F1= -F2 (Newtons 3rd law).

But the collision time is the same for both the bodies, t1 = t2.

Impulse of body 1 = F1*t1 and body 2 = F2*t2

F1*t1 = F1*t2 = -F2*t2 ,

Impulse = F * t , thus Impulse 1 = - Impulse 2

Impulse = change in momentum (by second law of Newton) , thus , m1 * v1 = - m2 * v2 , thus this implies momentum gained by one body = momentum lost by another body.

mgh=ms∆T10*200*1=4200∆T∆T=0.23°C

mgh=ms∆T10*200*1=4200∆T∆T=0.23

mass of girl = 50kg

mass of trolley = 10kg

Total mass,m= (50+10) = 60 kg

u =5m/s,v= 0,s= 12.5 m.

Using kinematics equation,v2=u2+ 2as

⇒ 0 = (5)2+ 2a(12.5)

⇒ 25a= –25

⇒a= –1m/s2

Force exerted on trolley, F =ma= 60×1 = 60N

(a) Work done on trolley W = FS = (60N) (12.5 m) = 750J

(b) Work done by the girl, W = FS

= (mass of girl) × retardation × S

= 50 × 1 × 12.5

= 625 J

thank you

Ans :- Eatinga varied, well-balanceddietmeans eatingavarietyoffoodsfrom eachfood groups daily, intherecommended amounts. It is also important to choose a varietyoffoodsfrom within eachfood group because differentfoodsprovide different types and amounts of key nutrients.