Answer:
Yes it is possible to control to some extent.
Explanation:
In general there are two types of magnets : permanent and temporary (electromagnets).
Electromagnets can be controlled since it basically depends on electricity. By switching on and off the electric supply the magnets also can be switched on and off respectively. We can also control the intensity of magnetic power.
On the other hand permanent magnet cannot be switched on and off but the magnetic properties can be altered event to an extent when it loses all its magnetic properties. It can be caused by high temperature, physical impact and also exposure to other magnetic fields. For every element there is a point of temperature called curie temperature above which the permanent magnet loses its magnetic properties. This can be brought back again by induced magnetism. The only issue is that induced magnetism work in most cases but not in all.
Speed of Ferry is towards North with magnitude 6.2 m/s
Here if we assume that North direction is along Y axis and East is along X axis then we can say
Now a person walk on ferry with speed 1.5 m/s towards east with respect to Ferry
so it is given as
also by the concept of relative motion we know that
now plug in all values in it
now if we need to find the speed of the person then we need to find its magnitude
so it is given as
Answer
• Improving the environmental performances
• Developing Green Mining technology
Explanation
The effect to the environment caused by opal mining are; impact on soils and geology, clearing of native vegetation disrupting flora and fauna, change in land use and effects of air quality.
Opal mining is currently examining environmental impacts and adopting measures that mitigate the impacts making the process less destructive to the environment.
With the current commitment to sustainability, opal companies are investing funds for Green Mining as a positive way to impact the environment before and after mining.
Net force on the car=F=4.8 x 10³ N
Explanation:
mass of car= 1.2 x 10³ Kg
initial velocity= Vi=0
Final velocity= Vf= 20 m/s
time = t= 5 s
Using kinematic equation,
Vf= Vi + at
20= 0 + a (5)
5 a=20
a= 20/5
a= 4 m/s²
Now force is given by F = ma
F= 1.2 x 10³ (4)
F=4.8 x 10³ N
Complete Question
The complete question is shown on the first uploaded image
Answer:
a
b
New 
Explanation:
From the question we are told that
The refractive index of the core is 
The refractive index of the cladding is 
Generally according to Snell's law
Where 
is the largest angle a largest angle a ray will make with respect to the interface of the fiber and experience total internal reflection
![\theta_{max} = 90 - sin^{-1} [\frac{n_{cladding}}{n_{core}} ]](https://tex.z-dn.net/?f=%5Ctheta_%7Bmax%7D%20%3D%2090%20-%20sin%5E%7B-1%7D%20%5B%5Cfrac%7Bn_%7Bcladding%7D%7D%7Bn_%7Bcore%7D%7D%20%5D)
![\theta_{max} = 90 - sin^{-1} [\frac{1.421}{1.497}} ]](https://tex.z-dn.net/?f=%5Ctheta_%7Bmax%7D%20%3D%2090%20-%20sin%5E%7B-1%7D%20%5B%5Cfrac%7B1.421%7D%7B1.497%7D%7D%20%5D)
Given from the question the the largest angle is 5°
Generally the refraction index of the cladding is mathematically represented as
