Answer:
L = 2.8 cm
Explanation:
Period T = 4 / 12 = 1/3 s
T = 2π√(L/g)
L = (T/2π)²g
L = ((1/3)/2π)²9.8 = 0.02758... ≈ 2.8 cm
Answer:
d = 90 ft
Explanation:
Here in each swing the distance sweeps by the swing is half of the initial distance that it will move
So here we can say that total distance in whole motion is given as

since it is half of the distance that it will move in each swing so it would be a geometric progression with common ratio of 1/2
so sum of such GP is given by the formula



4 blocks north because he is it not asking for north east
Answer:
B'= 3.333 B
Explanation:
Lets take
Initial area = A
Magnetic field = B
The area after compression
A'=0.3 A
Magnetic field = B'
We know that flux ,Ф
Ф = B A
Given that flux is constant so
B A = B' A'
B A=B' x 0.3 A
B'= 3.333 B
It means that magnetic field will increase.