Explanation:
d frequency I learned it last year
Answer:
0.02585 BTU
Explanation:
Given: Spring constant, k = 270 lbf/in
Initial force, f =100 lbf
Compression, x = 1 in
Work done can be calculated as follows:

Here if we assume that there is no air friction on both balls then we can say

now the acceleration is given as


so here both the balls will have same acceleration irrespective of size and mass
so we can say that to find out the time of fall of ball we can use


now from above equation we can say that time taken to hit the ground will be same for both balls and it is irrespective of its mass and size
the correct choice is
C) an electric current.
as a magnet is turned quickly relative to a coil, the magnetic flux linked with coil varies due to variation of angle of direction of magnetic field with normal to the plane of coil. the coil resist this change of magnetic flux in it by inducing emf in it so as to nullify the variation in magnetic flux. Due to this induced emf , electric current flows through the coil.
The frequency of a wave is the number of waves that passes through a point in a certain time. The less waves that pass in a period of time the lower the frequency of the wave. The more waves that pass in a period of time the higher the frequency of the wave. When measuring wave length the time period used is usually one second.