<span>120 miles is the answer
</span>
Answer:
Heat
Friction is what causes heat.
Brainliest always helps.
Answer:
(a) 
(b) 
Explanation:
(a) The surface current density of a conductor is the current flowing per unit length of the conductor.

Considering a wire, the current is uniformly distributed over the circumferenece of the wire.

The radius of the wire = a

The surface current density 
(b) The current density is inversely proportional
......(1)
k is the constant of proportionality

........(2)
substituting (1) into (2)





substitute 

26.54 m/s is the magnitude of its velocity just before it strikes the ground
h=100m,v=20m/s,g=9.8m/s
time it takes to reach the ground,
![[t=\sqrt2h/g],[=\sqrt2*100/9.8=4.51s]](https://tex.z-dn.net/?f=%5Bt%3D%5Csqrt2h%2Fg%5D%2C%5B%3D%5Csqrt2%2A100%2F9.8%3D4.51s%5D)
x= 120m
t= 4.52
v= x/t
v= 120/4.52
v= 26.54 m/s
The "speed at which an object changes its location" can be expressed using a vector number called velocity. Consider a person who moves swiftly while taking two steps forward and two steps back while remaining in one location. Velocity is a vector quantity. Therefore, velocity is cognizant of direction. The direction must be taken into account when determining an object's velocity. A speed of 55 mph is not enough information. The direction must be used to appropriately depict the item's velocity. Simply said, the direction of the velocity vector indicates the direction of motion of an object.
To know more about velocity visit : brainly.com/question/16379705
#SPJ9
The basic difference is that the ordinary sources are incoherent that means that the discrete frequencies merge up to give an intermediate between the maximum and minimum frequencies. While the laser is coherent containing the single frequency with maximum amplitude. thus travelling far.