Answer:
The new self inductance is 3 times of the initial self inductance.
Explanation:
The self inductance of a solenoid is given by :

Where
N is number of turns per unit length
A is area of cross section
l is length of solenoid
If length and number of coil turns are both tripled,
l' = 3l and N' = 3N
New self inductance is given by :

So, the new self inductance is 3 times of the initial self inductance.
The correct answer is compound
The correct answer would be the last one
Answer:
1.56 m/s
Explanation:
For East direction, the 6 blocks is equivalent to 6*100=600 m
For West direction, 8 blocks is equivalent to 8*100=800 m
Speed is given by s=d/t where s is speed, d is distance covered and t is time taken
Total distance is 600+800=1400m
Time taken is 15 mins, converted to seconds will be 15*60=900 s
Speed, s=1400/900=1.5555555555555 m/s rounded off as 1.56 m/s