Answer:

Explanation:
The free body diagram of the block on the slide is shown in the below figure
Since the block is in equilibrium we apply equations of statics to compute the necessary unknown forces
N is the reaction force between the block and the slide
For equilibrium along x-axis we have

Using value of N from equation β in α we get value of force as

Applying values we get

Answer:
c
Explanation:
Your <em><u>wheels lose traction</u></em> on the road and your car <em><u>skids</u></em>
Answer:
the wavelength λ of the light when it is traveling in air = 560 nm
the smallest thickness t of the air film = 140 nm
Explanation:
From the question; the path difference is Δx = 2t (since the condition of the phase difference in the maxima and minima gets interchanged)
Now for constructive interference;
Δx= 
replacing ;
Δx = 2t ; we have:
2t = 
Given that thickness t = 700 nm
Then
2× 700 =
--- equation (1)
For thickness t = 980 nm that is next to constructive interference
2× 980 =
----- equation (2)
Equating the difference of equation (2) and equation (1); we have:'
λ = (2 × 980) - ( 2× 700 )
λ = 1960 - 1400
λ = 560 nm
Thus; the wavelength λ of the light when it is traveling in air = 560 nm
b)
For the smallest thickness 
∴ 



Thus, the smallest thickness t of the air film = 140 nm
Answer:
Earth's axis is tilted relative to its orbital plane.
Earth orbits around the Sun, completing one orbit each year
Explanation:
The earth tilt at an angle causes the sun rays to hit the earth surface around the globe differently. Due to the oblique angle that the rays hit the subtropics and poles, there is less heat intensity compared to the equator where the sun rays hit the earth's surface at a more or less right angle.
The earth rotation around the sun also causes seasons coupled with the earth’s tilts. As the earth rotates, in one point in the orbit, the northern or southern hemispheres will be tilted towards the sun. The phenomenon varies the local temperatures of particular regions of the earth hence driving seasonal climatic changes.
Given:
I=8A
t=2second
Potential difference,V=120-100=20volt
Workdone=V×i×t
=20×8×2
=320 joule.