Physics

Physics Dual Nature of Radiation and Matter

Contributor-Level 10

$β = 12 m m = 12 * 1 0^{- 3} m$

$\begin{array}{l} β' = \frac{β}{μ} = \frac{12 * 1 0^{- 3}}{4 / 3} = 9 * 1 0^{- 3} m \\ β' = 9 m m \end{array}$

0 0

New answer posted

8 months ago

A parallel beam of light of wavelength 900nm and intensity 100Wm^-2 is incident on a surface perpendicular to the beam. The number of photons crossing 1cm² area perpendicular to the beam in one second is

0 Follower 2 Views

Contributor-Level 10

$E = I A$

$= 100 * 1 * 1 0^{- 4}$

$= 1 0^{- 2} W$

$E = n h \frac{c}{λ}$

$1 0^{- 2} = \overset{?}{n} * \frac{6.64 * 1 0^{- 34} * 3 * 1 0^{8}}{900 * 1 0^{- 9}}$

$\overset{?}{n} = \frac{1 0^{- 2} * 9 * 1 0^{- 7}}{6.64 * 1 0^{- 34} * 3 * 1 0^{8}}$

$\overset{?}{n} = 4.5 * 1 0^{16}$

0 0

New answer posted

8 months ago

Physics Physics Nuclei

The disintegration rate of a certain radioactive sample at any instant is 4250 disintegrations per minutes later, the rate becomes 2250 disintegrations per minute. The approximate decay constant is:

(Take log₁₀ 1.88 = 0.274)

0 Follower 5 Views

Physics Physics Electromagnetic Waves

Contributor-Level 10

$A = A o e^{- λ t}$

$\Rightarrow 2250 = 4250 e^{- λ t}$

$\Rightarrow λ * 10 * 0.434 = 0.274$

$\Rightarrow λ = \frac{0.274}{10 * 0.434} = 0.63 m i n^{- 1}$

0 0

New answer posted

8 months ago

A radio can tune to any station in 6 MHz to 10 MHz band. The value of corresponding of wavelength bandwidth will be

0 Follower 2 Views

Contributor-Level 10

$λ_{1} = 6 M H z = 6 * 1 0^{6} H z$

$λ_{1} = \frac{C}{υ_{1}} = \frac{3 * 1 0^{8}}{6 * 1 0^{6}} = 50 m$

$λ_{2} = \frac{C}{υ_{2}} = 10 * 1 0^{6} = \frac{3 * 1 0^{8}}{10 * 1 0^{6}} = 30 m$

Wavelength bandwidth

$= | λ_{1} - λ_{2} | = 20 m$

0 0

New answer posted

8 months ago

Three masses M = 100kg, m₁ = 10kg and M₂ = 20kg are arranged in a system as shown in figure. All the surface are frictionless and strings are inextensible and weightless. The pulleys are also weightless and frictionless. A force F is applied on the system so that the mass m₂ moves upward with an acceleration of 2ms^-2. The value of F is:

(Take g = 10ms^-2)

0 Follower 762 Views

Contributor-Level 10

Given Acceleration of m₂ is 2m/s²

(upward)

N = 20a T – m₂g = m₂a

T – 20g = 20a

T = 200 + 20 * 2

T = 240 N

T = m₁ a₁

240 = 10a₁

a₁ = 24 m/s²

$\Rightarrow T a + T a_{1} - T a_{2} = 0$

$a_{2} = 24 + 2 = 26 m / s^{2}$

F – T – N = Ma₂

F – 240 = 100 * 26 + 20 * 26

F = 3360 N

0 0

New answer posted

8 months ago

Is every oscillatory motion a simple harmonic motion?

0 Follower 1 View

Contributor-Level 10

No, only oscillations with a linear restoring force and sinusoidal motion are SHM. Non-linear oscillations, such as large pendulum swings, deviate from SHM.

0 0

New answer posted

8 months ago

What is the difference between oscillations and vibrations?

0 Follower 2 Views

Contributor-Level 10

Oscillations are larger, slower to-and-fro motions. Vibrations, on the other hand, are smaller, faster oscillations. Vibrations often occur in machines, strings, and structural components.

0 0

New answer posted

8 months ago

Can all periodic motions be oscillatory?

0 Follower 3 Views

Contributor-Level 10

No, periodic motion isn't always oscillatory. It may not involve back-and-forth movement about an equilibrium point. Some known examples include circular motion in satellites or planets.

0 0

New answer posted

8 months ago

Is a simple pendulum the same as a simple harmonic motion?

0 Follower 1 View

Contributor-Level 10

A simple pendulum shows simple harmonic motion only for small angular displacements. Otherwise, its motion is oscillatory but not purely SHM.

0 0

New answer posted

8 months ago

What are the forces acting on a swinging pendulum?

0 Follower 1 View