Answer:
A) v = 40 m / s, B) v_average = 20 m / s
Explanation:
For this exercise we will use the kinematics relations
A) the final velocity for t = 5 s and since the body starts from rest its initial velocity is zero
v = vo + a t
v = 0 + 8 5
v = 40 m / s
B) the average velocity can be found with the relation
v_average = vf + vo / 2
v-average = 0+ 40/2
v_average = 20 m / s
Answer:The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener.
As the source of sound waves approaches a listener, the sound waves get closer together, increasing their frequency and the pitch of the sound. The opposite happens when the source of sound waves moves away from the listener.
Explanation:
At the instant the second bulb is connected ...
... the brightness of the <u>first bulb</u> doesn't change
... the brightness of the <u>second bulb</u> changes from dark (no brightness) to equal to the first bulb
The efficiency of the machine is defined as
Here
Work out is the work output and Work in is the work input
To find the Work in we have then
Replacing with our values
The work done by the applied force is
W = Fd
Here,
F = Force
d = Distnace
Rearranging to find F,
F = 129.77N
Therefore the force exerted on the machine after rounding off to two significant figures is 130N
