Answer:

Explanation:
Force on a current carrying rod due to magnetic field is given as

here we know that
current in the rod


now magnetic force is balanced by the weight of the rod
so we will have



Answer:
Explanation:
Since the front and back of the rocket simultaneously line up with forward and backward end of the platform respectively .
Then length of the platform = length of the train rocket .
A )
Time to cross a particular point on the platform
= length of rocket train / .96 x 3 x 10⁸
= 90 / .96 x 3 x 10⁸
= 31.25 x 10⁻⁸ s
B) Rest length of the rocket = length of platform = 90 m
C ) length of platform as viewed by moving observer =

= 
= 321 m
D ) For the observer on platform time taken = 31.25 x 10⁻⁸ s
for the observer in the rocket , time will be dilated so time recorded by observer in motion ,
8.75 x 10⁻⁸ s .
Density is the characteristic property of a substance. It is the measure of mass of the substance
divided by its volume (density= mass/volume). Manipulate the given formula to
come up with the formula for the volume. Therefore, volume is equals to mass of
a substance divided by its density (Vol= mass/density). Given 12.6 g/ml as density
and 7.65 g mass, volume is equals to 0.60714 ml, since 1 ml = 1cm^3, volume is
equals to 0.60714 cm^3 then extract the cube root of the volume to get the
length of the cube in cm which is equal to 0.84677 cm.
Complete Question
The complete question is shown on the first uploaded image
Answer:
The angle between shuttle's velocity and the Earth's field is 
Explanation:
From the question we are told that
The length of eire let out is 
The emf generated is 
The earth magnetic field is 
The speed of the shuttle and tether is 
The emf generated is mathematically represented as

making
the subject of the formula
![\theta = sin ^{-1}[ \frac{\epsilon}{L * B *v} ]](https://tex.z-dn.net/?f=%5Ctheta%20%3D%20%20%20sin%20%5E%7B-1%7D%5B%20%5Cfrac%7B%5Cepsilon%7D%7BL%20%20%2A%20B%20%20%2Av%7D%20%5D)
substituting values
![\theta = sin ^{-1}[ \frac{40}{250 * (5*10^{-5}) *(7.80 *10^{3})} ]](https://tex.z-dn.net/?f=%5Ctheta%20%3D%20%20%20sin%20%5E%7B-1%7D%5B%20%5Cfrac%7B40%7D%7B250%20%20%2A%20%285%2A10%5E%7B-5%7D%29%20%20%2A%287.80%20%2A10%5E%7B3%7D%29%7D%20%5D)
