Yes. Since the wavelength of the red line in the Hydrogen spectrum is 656.5 nanometer. This confirms the possibility of seeing the spectral line with the same wavelength in the absorption spectrum of hydrogen atoms. The Hydrogen spectrum has the lower limit of 656.5 nm which still includes 656.5 nm in the range.
Answer:
F > W * sin(α)
Explanation:
The force needed for the box to start sliding up depends on the incline (α).
The external forces acting on the box would be the weight, the normal reaction and the lifting force that is applied to make it slide up.
These forces can be decomposed on their normal and tangential (to the slide plane) components.
The weight will be split into
Wn = W * cos(α) (in normal direction)
Wt = W * sin(α) (in tangential direction)
The normal reaction will be alligned with the normal axis, and will be equal to -Wn
N = -W* cos(α) (in normal direction)
To mke the box slide up, a force must be applied, that is opposite to the tangential component of the weight and at least a little larger
F > |-W * sin(α)| (in tangential direction)
In order for the object not to slip, the component of the weight parallel to the surface must be equal to the frictional force (which acts in the opposite direction):

The parallel component of the weight is:

where m is the object mass and

is the angle of the inclined plane.
The frictional force is

where

is the coefficient of static friction.
Equalizing the two forces, we have

from which we find

and so, in our problem the coefficient of static friction must be
Weight of object = mass x acceleration due to gravity
= 2.5 x 9.8
= 24.5N
Hence option B is correct.
Hope this helps!!
Answer: Current in a wire
We can use the same right-hand rule as we did for the moving charges—pointer finger in the direction the current is flowing, middle finger in the direction of the magnetic field, and thumb in the direction the wire is pushed.
Explanation: