Answer:
the thermal energy generated in the loop = 
Explanation:
Given that;
The length of the copper wire L = 0.614 m
Radius of the loop r = 
r = 
r = 0.0977 m
However , the area of the loop is :



Change in the magnetic field is 
Then the induced emf e = 
e = 
e = 2.74 × 10⁻³ V
resistivity of the copper wire
Ω m
diameter of the wire = 1.08 mm
radius of the wire = 0.54 mm = 0.54 × 10⁻³ m
Thus, the resistance of the wire R = 
R = 
R = 1.13× 10⁻² Ω
Finally, the thermal energy generated in the loop (i.e the power) = 
= 
= 
Answer:
Explanation:
Yes I agree with the statement .
When a person who is perfectly insulated from the earth , touches a Van de Graaff , his body acquires charge . when the hair acquires it, it stands out due to mutual repulsion . It is to be noted here that at pointed areas on a surface , there is larger accumulation of charge. Accumulation of charge is greater at hair tops .
It is also a general observation that when a bird sits on high tension wire , his feather stands out due to the same reason.
Answer:
(a) 
(b) 
(c) 1 s
(d) 20 m
(e) 1 m
(f) 
(g) 
(h) 
(i) 
(j) 
(k) 
(l) 
(m) 
Explanation:
Since <em>x</em> is measured in meters and <em>t</em> in seconds, constants <em>a </em>and <em>b</em> must have units that gives meters when multiplied by square and cubic seconds respectivly, so that would mean
for <em>a </em>and
for <em>b</em>.
We can get the velocity <em>v </em>equation by deriving the position with respect to <em>t</em>, which gives:

And the acceleration <em>a</em> equation by deriving again:

Now for getting the maximun position between 0 and 4, we must find to points where the positions first derivate is equal to cero and evaluate those points. That is <em>v=0</em>, which gives

For <em>t = 0</em>,<em> x = 0</em> so the maximun position is archieved at 1 second, which gives <em>x = 1 meter</em>.
For obtaining it's displacement <em>r</em>, we can integrate the velocity from 0 seconds to 4 seconds, which gives the mean value of the position in that interval:

For the remaining questions, we just replace the values of <em>t</em> on the respective equations.
Answer:
OPTION A is the correct answer
No additional force is required because it's already going downhill