Both positive work and negative work have meaning: Positive work follows when the force has a component parallel to the displacement. Positive work adds energy to a system. Negative work follows when the force has a component opposite or against the displacement.
No. It is D. Science is actually testable. That is the purpose of the scientific method: to TEST a theory. For something to be considered science, you must be able to observe, ask questions, develop questions, and test them. Thefore, it is a process. Lastly, yes. Science is a body of knowledge. It's a subject field that covers many things and numerous sub areas.
Answer:
Explanation:
Given
Let us suppose police car and motorist travel in straight line and police car catches motorist after s distance
Distance travel by motorist
----1
Distance traveled by Police car
![s=ut+\frac{at^2}{2}](https://tex.z-dn.net/?f=s%3Dut%2B%5Cfrac%7Bat%5E2%7D%7B2%7D)
![s=0+\frac{a_pt^2}{2}](https://tex.z-dn.net/?f=s%3D0%2B%5Cfrac%7Ba_pt%5E2%7D%7B2%7D)
----2
from 1 & 2 we get
![t=\frac{2v_m}{a_p}](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B2v_m%7D%7Ba_p%7D)
(a)Velocity of Police car after t sec
![v=u+a_pt](https://tex.z-dn.net/?f=v%3Du%2Ba_pt)
![v=0+a_p\times \frac{2v_m}{a_p}](https://tex.z-dn.net/?f=v%3D0%2Ba_p%5Ctimes%20%5Cfrac%7B2v_m%7D%7Ba_p%7D)
![v=2v_m](https://tex.z-dn.net/?f=v%3D2v_m)
(b)time taken by police car is
![t=\frac{2v_m}{a_p}](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B2v_m%7D%7Ba_p%7D)
(c)Distance travel by police car![=\frac{2v_m^2}{a_p}](https://tex.z-dn.net/?f=%3D%5Cfrac%7B2v_m%5E2%7D%7Ba_p%7D)
Answer:
r = 0.05 m = 5 cm
Explanation:
Applying ampere's law to the wire, we get:
![B = \frac{\mu_oI}{2\pi r}\\\\r = \frac{\mu_oI}{2\pi B}](https://tex.z-dn.net/?f=B%20%3D%20%5Cfrac%7B%5Cmu_oI%7D%7B2%5Cpi%20r%7D%5C%5C%5C%5Cr%20%3D%20%20%5Cfrac%7B%5Cmu_oI%7D%7B2%5Cpi%20B%7D)
where,
r = distance of point P from wire = ?
μ₀ = permeability of free space = 4π x 10⁻⁷ N/A²
I = current = 2 A
B = Magnetic Field = 8 μT = 8 x 10⁻⁶ T
Therefore,
![r = \frac{(4\pi\ x\ 10^{-7}\ N/A^2)(2\ A)}{2\pi(8\ x\ 10^{-6}\ T)}\\\\](https://tex.z-dn.net/?f=r%20%3D%20%5Cfrac%7B%284%5Cpi%5C%20x%5C%2010%5E%7B-7%7D%5C%20N%2FA%5E2%29%282%5C%20A%29%7D%7B2%5Cpi%288%5C%20x%5C%2010%5E%7B-6%7D%5C%20T%29%7D%5C%5C%5C%5C)
<u>r = 0.05 m = 5 cm</u>