Answer:
2 seconds
Explanation:
The frequency of a wave is related to its wavelength and speed by the equation

where
f is the frequency
v is the speed of the wave
is the wavelength
For the wave in this problem,
v = 2 m/s

So the frequency is

The period of a wave is equal to the reciprocal of the frequency, so for this wave:

This means that the wave takes 4 seconds to complete one full cycle.
Therefore, the time taken for the wave to go from a point with displacement +A to a point with displacement -A is half the period, therefore for this wave:

Answer:
D) 11 m/s
Explanation:
The problem asks us to calculate the velocity of the hot dog with respect to the observer stationary outside the train. This velocity is given by:

where
is the velocity of the train (towards right)
is the velocity of the man (towards right)
is the velocity of the hot-dog (towards left, so we put a negative sign)
Substituting the numbers into the equation, we find

and the positive sign means the velocity is toward right.
The motor effect is the term used when a current-carrying wire in the presence of a magnetic field experiences a force.
Gravity causes a falling object to fall 9.8 m/s faster every second it falls.
Kenny's book started out with no speed when it was dropped.
1.5 sec later, it was falling at (9.8 x 1.5) = 14.7 m/s .
During the fall, its average speed was 1/2(0 + 14.7) = 7.35 m/s .
Distance it covered = (average speed) x (time) =
(7.35 m/s) x (1.5 sec) = 11.025 m
<span>When picking up a load, the correct fork spacing must be spaced in an evenly manner in which the centre stringer of the pallet and the balance of the load should be spaced evenly in which makes the picking up the load to be correct and well-balanced.</span>