1. is D. Scientific method cannot be replaced.
2. is B.
3. is B as well.
A pendulum is not a wave.
-- A pendulum doesn't have a 'wavelength'.
-- There's no way to define how many of its "waves" pass a point
every second.
-- Whatever you say is the speed of the pendulum, that speed
can only be true at one or two points in the pendulum's swing,
and it's different everywhere else in the swing.
-- The frequency of a pendulum depends only on the length
of the string from which it hangs.
If you take the given information and try to apply wave motion to it:
Wave speed = (wavelength) x (frequency)
Frequency = (speed) / (wavelength) ,
you would end up with
Frequency = (30 meter/sec) / (0.35 meter) = 85.7 Hz
Have you ever seen anything that could be described as
a pendulum, swinging or even wiggling back and forth
85 times every second ? ! ? That's pretty absurd.
This math is not applicable to the pendulum.
Acceleration = (change in speed) / (time for the change)
change in speed = (speed at the end) - (speed at the beginning)
change in speed = (37 km/hr) - (89 km/hr) = -52 km/hr
Acceleration = (-52 km/hr) / (6 sec)
Acceleration = (-26/3) km/(hr·sec)
Units: (1/hr·sec) · (hr/3600 sec) = 1 / 3600 sec²
(-26/3) km/(hr·sec) = (-26/3) km/(3600 sec²)
= -26,000/(3 · 3600) m/s²
<em>Acceleration = -2.41 m/s²</em>
