The wavelength of the first order bright band light light is 714 nm .
Explanation:
We have to find the wavelength of the first order brightness of a light. Here we are using Huygen's principle of light.
The formula is
nλ =d sinθ
where, n is the order of maximum
λ is the wavelength of light
d is the distance between the lines on diffraction grating.
θ is the angle.
For the given equation n is 1 because the problem states that the light forms 1st order bright band
λ is unknown.
d =
or 0.0000014 m
sin (30) = 0.5
so,
1(λ) = (0.0000014)(0.5)
= 0.0000000714
= 714 nm
Thus, The wavelength of the first order bright band light light is 714 nm .
Answer:
is the compression in the spring
Explanation:
Given:
- mass of the bullet,

- mass of block,

- stiffness constant of the spring,

- initial velocity of the spring just before it hits the block,

<u>Now since the bullet-mass gets embed into the block, we apply the conservation of momentum as:</u>



Now this kinetic energy of the combined mass gets converted into potential energy of the spring.



is the compression in the spring
Answer:
2.068 x 10^6 m / s
Explanation:
radius, r = 5.92 x 10^-11 m
mass of electron, m = 9.1 x 10^-31 kg
charge of electron, q = 1.6 x 10^-19 C
As the electron is revolving in a circular path, it experiences a centripetal force which is balanced by the electrostatic force between the electron and the nucleus.
centripetal force = 
Electrostatic force = 
where, k be the Coulombic constant, k = 9 x 10^9 Nm^2 / C^2
So, balancing both the forces we get



v = 2.068 x 10^6 m / s
Thus, the speed of the electron is give by 2.068 x 10^6 m / s.
Answer:
F = 51.3°
Explanation:
The component of weight parallel to the inclined plane must be responsible for the rolling back motion of the car. Hence, the force required to be applied by the child must also be equal to that component of weight:

where,
W = Weight of Wagon = 150 N
θ = Angle of Inclinition = 20°
Therefore,

<u>F = 51.3°</u>
Answer:

Explanation:
Static friction occurs when an object initially starts at rest. When the surfaces of the materials touch, the microscopic unevenness interlock greatest with each other, causing the most friction out of the three.
During sliding friction, an object is already moving or in motion. The microscopic surfaces still interlock, but because the object is in motion, it has a momentum. Therefore, the magnitude of sliding friction is less than that of static friction.
Rolling friction occurs when an object rolls across some surface. Rather than surfaces interlocking, rolling friction is caused by the constant distortion of surfaces. As it rolls, the surfaces of the object are constantly wrapping and changing. This distortion causes the rolling friction. However, it is much less in magnitude when compared to static or sliding friction.