Answer:
0.495 m/s
Explanation:
= tension force in the string connecting the two objects
= Mass of the object on inclined plane = 250 g = 0.250 kg
= Mass of the hanging object = 150 g = 0.150 kg
= acceleration of each object
From the force diagram, force equation for the motion of the object on the inclined plane is given as

From the force diagram, force equation for the motion of the hanging object on the inclined plane is given as

Using the above two equations



= height dropped by the hanging object = 10 cm = 0.10 m
= Speed gained by the object
Speed gained by the object can be given as

Answer:
a) 
b) infrared region
Explanation:
Photon energy is the "energy carried by a single photon. This amount of energy is directly proportional to the photon's electromagnetic frequency and is inversely proportional to the wavelength. If we have higher the photon's frequency then we have higher its energy. Equivalently, with longer the photon's wavelength, we have lower energy".
Part a
Is provide that the smallest amount of energy that is needed to dissociate a molecule of a material on this case 0.42eV. We know that the energy of the photon is equal to:

Where h is the Planck's Constant. By the other hand the know that
and if we solve for f we have:

If we replace the last equation into the E formula we got:

And if we solve for
we got:

Using the value of the constant
we have this:


Part b
If we see the figure attached, with the red arrow, the value for the wavelenght obtained from part a) is on the infrared region, since is in the order of 
Answer:
4cm
Explanation:
Magnification of the virtual image
= image distance / object distance
Given
Image distance = 60.0cm
Object distance = 15.0cm
Therefore,
Magnification = 60.0/15.0
= 4 cm
Answer:
641 nm.
Explanation:
Given that,
A transmission grating has 5200 slits/cm.
We need to find the longest wavelength that can be observed in the third order. Using grating equation as follows :
...(1)
d is slit spacing
No fo slit per unit length :

We know that, N = 1/d
For longest wavelength, θ = 90°
From equation (1)

Hence, the longest wavelength in third order for a transmission grating is 641 nm.