Tags Physics

Physics

Get insights from 5.6k questions on Physics, answered by students, alumni, and experts. You may also ask and answer any question you like about Physics

Follow Ask Question

5.6k

Questions

Discussions

Active Users

Followers

New answer posted

a year ago

Physics Ray Optics and Optical Instruments

The efficiency of a Carnot's engine, working between stem point and ice point, will be

0 Follower 3 Views

Payal Gupta

Contributor-Level 10

Steam point (T₁) = 100°C = 273 + 100 = 373 K

Ice point (T₂) = 0°C = 273 K

$η = (1 - \frac{T_{2}}{T_{1}}) * 100 = (1 - \frac{273}{373}) * 100 = 26.81 %$

0 0

New answer posted

a year ago

Physics Semiconductor Electronics

The variation of acceleration due to gravity (g) with distance (r) from the centre of the earth is correctly represented by: (Given R = radius of earth)

0 Follower 14 Views

Payal Gupta

Contributor-Level 10

$g \propto r 0 \leq r \leq R$

$g \propto \frac{1}{r^{2}} r > R$

0 0

New question posted

a year ago

Physics Semiconductor Electronics

The variation of acceleration due to gravity (g) with distance (r) from the centre of the earth is correctly represented by: (Given R = radius of earth)

0 Follower 3 Views

New answer posted

a year ago

Physics Laws of Motion

A thin circular ring of mass M and radius R is rotating with a constant angular velocity 2 rads^-1 in a horizontal plane about an axis vertical to its plane and passing through the centre of the ring. If two objects each of mass m be attached gently to the opposite ends of a diameter of ring, the will then rotate with an angular velocity (in rads^-1).

0 Follower 8 Views

Payal Gupta

Contributor-Level 10

By conservation of Angular momentum

L_i = L_f

$M R^{2} ω = (m R^{2} + 2 m R^{2}) ω'$

$\frac{2 M}{M + 2 m} = ω'$

$\Rightarrow$ $ω' = \frac{2 M}{M + 2 m}$

0 0

New answer posted

a year ago

Physics System of Particles and Rotational Motion

An object is thrown vertically upwards. At its maximum height, which of the following quantity becomes zero?

0 Follower 7 Views

Payal Gupta

Contributor-Level 10

At maximum height velocity (v) = 0

So, momentum = mv = m * 0 = 0

0 0

New answer posted

a year ago

Physics Electrostatic Potential and Capacitance

A person is standing in an elevator. In which situation, he experiences weight loss?

0 Follower 2 Views

Payal Gupta

Contributor-Level 10

F.B.D of person w.r.t. elevator

mg – N = ma

N = mg – ma

N decreases so, person experiences weight loss.

0 0

New answer posted

a year ago

Physics Electromagnetic Waves

An expression for a dimensionless quantity P is given by $P = \frac{α}{β} l o g_{e} (\frac{k t}{β t});$ where α and β are constants, x is distance; k is Boltzmann constant and t is the temperature. Then the dimensions of will be

0 Follower 3 Views

Payal Gupta

Contributor-Level 10

$P = \frac{α}{β} l o g_{e} (\frac{k t}{β x})$

$\frac{k t}{β x}$ = Dimensionless

$β = \frac{k t}{x} = \frac{[M L^{2} T^{- 2} k^{- 1}] [k]}{[L]}$

$\frac{α}{β} =$ dimensionless

= dimensionless of

= MLT²

0 0

New answer posted

a year ago

Physics The p-Block Elements

Production of iron in blast furnace follows the following equation

$F e_{3} O_{4} (s) + 4 C O (g) \to 3 F e (I) + 4 C O_{2} (g)$

When 4.640 kg of Fe₃O₄ and 2.520 kg of CO are allowed to react then the amount of iron (in g) produced is:

[Given : Molar Atomic mass (g mo^-1); Fe = 56

Molar Atomic mass (g mol^-1); O = 16

Molar Atomic mass (g mol^-1); C = 12]

0 Follower 2 Views

alok kumar singh

Contributor-Level 10

Moles of Fe₃O₄ = $\frac{4.64 * 1 0^{3}}{232} = 20$

Moles of CO = $\frac{2.52 * 1 0^{3}}{28} = 90$

So limiting reagent = Fe₃O₄

So moles of Fe formed = 60

Weight of Fe = 60 * 56 = 3360

0 0

New answer posted

a year ago

Physics Physics NCERT Exemplar Solutions Class 12th Chapter Thirteen

For the network shown below, the value of V_B – VA is_________ V.

0 Follower 3 Views

alok kumar singh

Contributor-Level 10

I= $\frac{15}{3} = 5 A$

$V_{B} + I * 1 ? 15 = v_{A}$

$v_{B} ? v_{A} = 15 ? 5 * 1$

= 10v

0 0

New answer posted

a year ago

Physics Ray Optics and Optical Instruments

A parallel beam of light is allowed to afall on a transparent spherical globe of diameter 30cm and refractive index 1.5. The distance from the centre of the globe at which the beam of light can converge is_________ mm.

0 Follower 6 Views

alok kumar singh

Contributor-Level 10

When object is at infinity

u = $\infty, μ_{1} = 1, R = 15 c m$

v = ? $μ_{2} = 1.5$

$\frac{- μ_{1}}{u} + \frac{μ_{2}}{v} = \frac{μ_{2} - μ_{1}}{R}$

$\frac{- 1}{\infty} + \frac{1.5}{v} =$ $\frac{1.5 - 1}{15}$

$\frac{1.5}{v} =$ $\frac{0.5}{15}$

v =

45cm

Now for Refraction through C2

u = + 15cm

v = ?

$μ_{1} = 1.5$

$μ_{2} = 1$

R = 15

$\frac{- μ_{1}}{u} + \frac{μ_{2}}{v} = \frac{μ_{2} - μ_{1}}{R}$

$\frac{- 1.5}{15} + \frac{1}{v} = \frac{1 - 1.5}{- 15}$

$\frac{- 1}{10} + \frac{1}{v} = \frac{1}{30}$

$\frac{1}{v} = \frac{1}{30} + \frac{1}{10} = \frac{4}{10}$

$v = \frac{30}{4} = + 7.5 c m$

from centre = 15 + 7.5 = 22.5 cm = 225mm

0 0

View All 2 Answers

Get authentic answers from experts, students and alumni that you won't find anywhere else

On Shiksha, get access to

67k Colleges
1.2k Exams
718k Reviews
1850k Answers

Community GuidelinesUser Points System

QuestionsDiscussionsTags

Need guidance on career and education? Ask our experts

Your Question

Physics

Questions

Discussions

Active Users

Followers

All

Discussions

Unanswered Questions

Share Your College Life Experience