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

10 months ago

Physics Class 11th

Given below are two statements:

Statement I : A second's pendulum has a time period of 1 second.

Statement II : It takes precisely one second to move between the two extreme positions.

In the light of the above statements, choose the correct answer from the options given below:

0 Follower 2 Views

Vishal Baghel

Contributor-Level 10

Time period of second pendulum is 2 seconds. &nbs

...more

0 0

New answer posted

10 months ago

Physics Class 12th

A wire of $1 Ω$ has a length of 1m. It is stretched till its length increases by 25%. The percentage change in resistance to the nearest integer is:

0 Follower 6 Views

Vishal Baghel

Contributor-Level 10

$R_{i} = \frac{ρ l}{A}$

$R_{f} = \frac{ρ (1.25 l)}{(A / 1.25)} = {(1.25)}^{2} * \frac{ρ l}{A}$

$\Rightarrow R_{f} = 1.5625 * R_{i}$

$\Rightarrow \frac{R_{f} - R_{l}}{R_{l}} * 100 = 56.25 %$

0 0

New answer posted

10 months ago

Physics Physics Waves

The mass per unit length of a uniform wire is 0.135 g/cm. A transverse wave of the form y = -0.21 sin(x + 30t) is produced in it, where x is in meter and t is in second. Then, the expected value of tension in the wire is x * 10^-2 N. Value of x is-----------. (Round-off to the nearest integer)

0 Follower 4 Views

Payal Gupta

Contributor-Level 10

$v = \frac{ω}{k} = \frac{30}{1} = 30 m / s$

$v = \sqrt[]{\frac{T}{μ}} \Rightarrow T = μ v^{2} = \frac{0.135 * 1 0^{- 3}}{1 0^{- 2}} * {(30)}^{2} = 12.15 N = 1215 * 1 0^{- 2} N$

0 0

New question posted

10 months ago

Physics Physics Ray Optics and Optical Instruments

Given below are two statements : one is labeled as Assertion A and the other is labeled as Reason R.

Assertion A : For a simple microscope, the angular size of the object equals the angular size of the image.

Reason R : Magnification is achieved as the small object can be kept much closer to the eye that 25cm and hence it subtends a large angle.

In the light of the above statements, choose the most appropriate answer from the options given below:

0 Follower 3 Views

New answer posted

10 months ago

Physics Physics Electromagnetic Waves

A radiation is emitted by 1000W bulb and it generates an electric field and magnetic field at P, placed at a distance of 2m.Th efficiency of the bulb is 1.25%. The value of peak electric field at P is x * 10^-1 V/m. Value of x is----------. (Rounded – off to the nearest integer)

[Take $ε_{0} = 8.85 * 1 0^{- 12} C^{2} N^{- 1} m^{- 2}, c = 3 * 1 0^{8} m s^{- 1}]$

0 Follower 7 Views

Payal Gupta

Contributor-Level 10

$l = \frac{1}{2} c ε_{0} E_{0}^{2} = η * (\frac{P}{4 π r^{2}})$ Here $η$ is the efficiency

$E_{0} = \sqrt[]{\frac{η P}{2 π r^{2} c ε_{0}}} = \sqrt[]{\frac{1.25}{100} * \frac{1000}{2 * 3.14 * 4 * 3 * 1 0^{8} * 8.85 * 1 0^{- 12}}}$

$\Rightarrow E_{0} = \sqrt[]{\frac{12.5}{8 * 3.14 * 3 * 8.85 * 1 0^{- 4}}} = 13.69 V m = 136.9 * 1 0^{- 1} V / m$

0 0

New answer posted

10 months ago

Physics Class 11th

A person standing on a balance inside a stationary lift measures 60 kg. The weight of that person if the lift descends with uniform downward acceleration of 1.8m/s² will be----------N. [g = 10 m/s²]

0 Follower 3 Views

Payal Gupta

Contributor-Level 10

mg – N = ma

N = m (g – a) = 60 * (10 – 1.8) = 60 * 8.2 = 492 N

0 0

New answer posted

10 months ago

Physics Electromagnetic Induction

An aeroplane, with its wings spread 10m, is flying at a speed of 180 km/h in a horizontal direction. The total intensity of earth's field at that part is 2.5 * 10^-⁴Wb/m² and the angle of dip is 60°. The emf induced between the tips of the plane wings will be………….

0 Follower 2 Views

Vishal Baghel

Contributor-Level 10

Bv = B sin 60°

$B_{v} = 2.5 * 1 0^{- 4} * \frac{\sqrt[]{3}}{2}$

$E m f = B_{v} * v * l = 2.5 * 1 0^{- 4} * \frac{\sqrt[]{3}}{2} * 180 * \frac{5}{18} * 1 = 108.25 * 1 0^{- 3} v o l t s$

0 0

New answer posted

10 months ago

Physics Thermodynamics

The internal energy (U), pressure (P) and volume (V) of an ideal gas are related as U = 3PV + 4. The gas is:

0 Follower 2 Views

Vishal Baghel

Contributor-Level 10

U = 3PV + 4

$\Rightarrow n C_{v} T = 3 P V + 4$

$\Rightarrow n * \frac{f R T}{2} = 3 P V + 4$

$\Rightarrow f = 6 + \frac{8}{P V}$

$\Rightarrow f > 6 \Rightarrow p o l y a t o m i c$

0 0

New answer posted

10 months ago

Physics Physics Alternating Current

In a series LCR resonant circuit, the quality factor is measured as 100. If the inductance is increased by two fold and resistance is decreased by two fold, then the quality factor after this change will be--------.

0 Follower 2 Views

Payal Gupta

Contributor-Level 10

As we know that Q = $\frac{ω L}{R}$

$\Rightarrow \frac{Q'}{Q} = \frac{L'}{R'} * \frac{R}{L} = (\frac{L'}{L}) * (\frac{R}{R'}) = 2 * 2 \Rightarrow Q' = 4 Q = 4 * 100 = 400$

0 0

New answer posted

10 months ago

Physics Physics Electrostatic Potential and Capacitance

If 'C' and 'V' represent capacity and voltage respectively then what are the dimensions of $λ$ where C/V = $λ$

0 Follower 3 Views

Vishal Baghel

Contributor-Level 10

$λ = \frac{c}{v} = \frac{Q^{3}}{W^{2}} = \frac{I^{3} T^{3}}{M^{2} L^{4} T^{- 4}} \Rightarrow [λ] = [M^{- 2} L^{- 4} T^{7} l^{3}]$

0 0

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

On Shiksha, get access to

66k Colleges
1.2k Exams
705k 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