C. The person's feet push backward on the sidewalk; the sidewalk pushes forward on the person.
This is due to our kick back motion forced on the sidewalk when we walk, and the resistance of us walking on it createsa push forward.
Hope this helps!
Answer:
200 Watts.
Explanation:
Power is defines as the amount of work expended per unit time. Mathematically, it is expressed as Power = Workdone/Time
Given parameters
Energy used up 100Joules
Distance moved by brick = 1 meters
Time taken by the machine = 0.5 secs
Power can also be written as Energy/Time
Required
We need to calculate the amount of power used up.
Power = 100J/0.5s
Power = 100/(1/2)
Power = 100 * 2/1
Power = 200Watts.
This shows that the machine would expend 200Watts of power
Answer:
Because Physics is mainly composited of math
Explanation:
If you really think about it the only way any science works is off maths, whether that be measuring the amount of NaOH to put into a solution or determening the amount of sugar you want in a cake it all relys on maths
Answer:
The speed of this light and wavelength in a liquid are 
and 442 nm.
Explanation:
Given that,
Wavelength = 650 nm
Index refraction = 1.47
(a). We need to calculate the speed
Using formula of speed
Where, n = refraction index
c = speed of light in vacuum
v = speed of light in medium
Put the value into the formula
(b). We need to calculate the wavelength
Using formula of wavelength
Where, 
= wavelength in vacuum
= wavelength in medium
Put the value into the formula
Hence, The speed of this light and wavelength in a liquid are and 442 nm.
