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Elastic energy per unit volume: E = 1/2 * Stress * Strain

Using Hooke's law: Strain = Stress/Y

E = (Stress)^2/2Y = F^2/2Y A^2 where A = πD^2/ 4E = 8F^2/π^2D^4Y

∴ E1/E2 = (D2/D1)^4 (∵ F and Y are same for both )GIven : D1/D2 = 1/2

E1/E2 = (2/1)^4 = 16/1

thanks

energy =(stress)²/(2×young's modulus)=S²/2Y

Let the initial velocity is U and given the maximum height is 45m , at which V = 0

so, v² = u²-2gh => u² =2*10*45=> u = √900 = 30m/s

now time when V = u/2 = 30/2 = 15m/s is

V = u -gt ==> 15 = 30-10t => t = 15/10 = 1.5sec

The same notes being played on sitar and veena differin quality. increasesWhen one of the prongs of the tuning forkisbroken, then the energyisused by the other prong. Hence, its amplitude and the intensity increases.

both quality and pitch

nagative point of stone

Let us consider an object which is projected vertically upwards with initial velocity u which reaches a maximum height h.Acceleration due to gravity=-gEquation of Motion for a body projected thrown upwards :V=u-gt----------(1)h=ut-1/2gt² -----------(2)v²-u²=-2gh --------(3)

Equations of motion for freely falling body :for free fall :Initial velocity=u=0g=gV=gt----------(4)h=1/2gt²-------(5)v²=2gh------(6)Time of Ascent is the time taken by body thrown up to reach maximum height hAt maximum height , V=0

Equation (1) turns to u=gt1t1=u/g ----------(7)Maximm height h=u²/2g ----------(8)

Time of descent : After reaching maximum height , the body begins to travel downward like free fallso equation (5) h=1/2gt₂²t₂²=2h/gt₂=√2h/gbut from equation (9)t₂=√2xu²/2g²t₂=u/g -----------------equation (10)∴t₁=t₂The time ascent is equal to time of descent in case of bodies moving under gravity.

From 3rd equation of motion v2 = u2 - 2gH0=u^2-2g (H/2)=u^2-gHH= u^2/g= ?10?^2/10 =10 m

thx

C = 4πeR

= 1/(9*10^9)

= 1.1*10^-10 F

Like my answer if you find it useful!

we know that, v= u+athere, v =0m/s a = - 9.8m/s square t= 2 s0= u+ (-9.8*2)or, 0= u-19. 6or, u= 19. 6the initial velocity of the ball is 19.6 m/s.

We also know, s= ut + 1/2 at. tso, s= 19. 6*2+1/2*(-9. 8)

Thepeelmakes the surface smooth, so the friction between our feet and ground decreases, causing us tofall whenwe stepon abanana peel.

Fluid friction is the force of friction exerted by fluids on objects movingthrough them.

Walking on smooth surfaces is difficult because friction is less.

10 in south east direction

Let east be +i ( +ve x axis) and north be +j ( +ve y axis)

now velocity of scooter Initial = 10i

if it turns right of east , mean he goes to southvelocity final = -10j

now change in speed = -10j-10i = √(10)²+(10)² = 10√2 = 14.14

direction is -i-j ( south west)

option 4

Convectionis the process of heat transfer from one location to the next by the movement of fluids. The moving fluid carries energy with it. The fluid flows from a high temperature location to a low temperature location.To understand convection in fluids, let's consider the heat transfer through the water that is being heated in a pot on a stove. Of course the source of the heat is the stove burner. The metal pot that holds the water is heated by the stove burner. As the metal becomes hot, it begins to conduct heat to the water. The water at the boundary with the metal pan becomes hot. Fluids expand when heated and become less dense. So as the water at the bottom of the pot becomes hot, its density decreases. Differences in water density between the bottom of the pot and the top of the pot results in the gradual formation ofcirculation currents. Hot water begins to rise to the top of the pot displacing the colder water that was originally there. And the colder water that was present at the top of the pot moves towards the bottom of the pot where it is heated and begins to rise. These circulation currents slowly develop over time, providing the pathway for heated water to transfer energy from the bottom of the pot to the surface.Convection also explains how an electric heater placed on the floor of a cold room warms up the air in the room. Air present near the coils of the heater warm up. As the air warms up, it expands, becomes less dense and begins to rise. As the hot air rises, it pushes some of the cold air near the top of the room out of the way. The cold air moves towards the bottom of the room to replace the hot air that has risen. As the colder air approaches the heater at the bottom of the room, it becomes warmed by the heater and begins to rise. Once more, convection currents are slowly formed. Air travels along these pathways, carrying energy with it from the heater throughout the room.

thxxxx very much mam

1.)Radiowavesare used for communications and radar.

2.)Microwaves are used to cook your food

like the answer if it helps you

1.Someexamples in everyday lifeinclude: rectangular tissue boxes, juice boxes, laptop computers, school notebooks and binders, standard birthday presents -- such as shirt boxes -- cereal boxes and aquariums. Larger structures, such as cargo containers, storage sheds, houses and skyscrapers are also rectangularprisms.

2.1)Convex lens is used in microscopes and magnifying glasses to subject all the light to a specific point.2) Convex lens is used as a camera lens in cameras as they focus light for a clean picture3) Convex lens is used in the correction of hypermetropia.4) The convex mirror is used as side-view mirror on the passenger side of a car because it forms an erect and smaller image for the way behind the car.

let the time period of oscillation be t.from question,t= k l^a m^b g^c

BY PRINCIPLE OF HOMOGENETY OF DIMENSIONS,M^0L^0T^1= L^a M^b (L^1 T^-2)^c=M^b L^a+c T^-2c

​THIS GIVES,b=0, a=1/2, c=-1/2

APPLYING THE VALUES INTO THE ASSUMED EQUATION 1,T=kl^1/2g1/2T= k sqr root l/ sqr root g

v=40m/sm= 10kgTaking g= 10m/s[Answer may varry if g=9.8m/s]

K.E=P.E

1/2mv^2=mgh1/2×10×(40)^2=10×10×h5×1600=100×h8000=100×h8000/100=hh=80m

At height of 80m , Kinetic energy= Potential energy

Fruits fall down due to inertia of rest when the branches of a tree are shaken. Fruits and branches are both at rest, but when branches of trees are shaken, branches starts moving where as fruits remain its state of rest and so separated from the branches and fall down. Dust particles on a carpet fall if we beat the carpet with a stick is another example for the inertia at rest. When we beat the carpet with a stick carpet starts moving, but the dust particles remains at its state of rest and separated from the carpet. With a quick pull, a table cloth can be removed from a dining table without disturbing dishes on it due to the Inertia of rest. The inertia of rest of the dishes keeps them where they are.__________________

Solution :- We know , acceleration is the change in velocity per unit time .e.g an instant time ; a = dv/dt a = dv/dt a∫dt = ∫dv now, integrate a.(t₂ - t₁) = v - u Let (t₂- t₁) = t then, at = v - u v = u + at ___ its a motion equation ,

now , v = u + at multiply both sides, with dt v.dt = u.dt + at.dt we know, v.dt = S { distance = speed * time } use this S = u(t₂-t₁) + a(t₂-t₁)²/2 hence, S = ut + 1/2at² ___motion, equation.

now, S = ut + 1/2at² ___(1) v = u + atsquaring both sides, v² = u² + a²t² + 2uat v² = u² + 2a{ 1/2at² + ut } from eqn (1) v² = u² + 2aS ____motion equation,

or we know, v.dv/dx = a ∫v.dv = a∫dx integrate both sides, v² - u² = 2a( x₂ - x₁) Let ( x₂ - x₁) = S v² = u² + 2aS___motion equation

Let us consider an object which is projected vertically upwards with initial velocity u which reaches a maximum height h.Acceleration due to gravity=-gEquation of Motion for a body projected thrown upwards :V=u-gt----------(1)h=ut-1/2gt² -----------(2)v²-u²=-2gh --------(3)

Equations of motion for freely falling body :for free fall :Initial velocity=u=0g=gV=gt----------(4)h=1/2gt²-------(5)v²=2gh------(6)Time of Ascent is the time taken by body thrown up to reach maximum height hAt maximum height , V=0

Equation (1) turns to u=gt1t1=u/g ----------(7)Maximm height h=u²/2g ----------(8)

Time of descent : After reaching maximum height , the body begins to travel downward like free fallso equation (5) h=1/2gt₂²t₂²=2h/gt₂=√2h/gbut from equation (9)t₂=√2xu²/2g²t₂=u/g -----------------equation (10)∴t₁=t₂The time ascent is equal to time of descent in case of bodies moving under gravity.

can u plzz once more send ...clear picture

your answer is correct

Weight of a body on moon is 1/6th of that on earth due to decreased acceleration of gravity.

Well, first we want to find the time in which the particle changes from a positive X speed, to a negative x speed, so we're looking for where x = 0.

If we use V = V0+at using initial velocity and acceleration, we get:0 = 3 + -1(t)t = 3

So, it changes direction along the x axis at 0, and that's it's max x. To find velocity, we use time and it's acceleration along the y axis, so...V = V0+atV = 0+.5(3)V = 1.5 = Answer (a)Hence, option (2) is correct.

find the slope y - intercept of the line given by the equation 2y - 3x =12

the weight decrease when put in water is 8 gm and in the unknown liquid is 24 gm therefore the buoyant force is 3 times in that of water hence it's density should be 3 time to that of waterthere fore answer should be c IE 3

c) is correct answer

If velocity of the body when It strikes the ground is v at an angle of 45°, then

Horizontal component of v =Initial horizontal velocity

It is because there is no force acting on the body horizontally and so velocity remains constant. Thus

v Cos 45°=horizontal component of velocity at the point of strike=18 m/s

The vertical component of the velocity=v Sin 45°=v Cos 45° (since Sin 45°=Cos 45°)

Thus vertical component of velocity of the body at the point of strike=v Cos45°

=18 m/s

True weight of body should be = sqrt (18 * 8)

= sqrt (144)

= 12 kg

ans is correct but how do you calculate it ? which concept is used here?!

Option (3) is correct.

thanks

b is the correct and

b is the correct answer

Radius of ring , R = 0.4/2 = 0.2 m mass of ring , M = 10 Kg

(i) moment of inertia , I = MR² I = 10 × (0.2)² = 10 × 0.04 = 0.4 Kg.m²

(ii) angular momentum , L = Iω∵ ω = 2πν , here I = 0.4 Kg.m² and ν = 1200rpm = 1200/60 r/s ∴ L = 0.4 × 2π × 1200/60 = 50.24 ≈ 50 Kgm²/s