Black hole Close-up of central region near black hole
Side ASide B
The picture on the right is a close-up of the central region in the picture on the
left. Based on the frequency shift, which side is rotating away from Earth?
Ans. B
A bat sends an ultrasonic wave that bounces off of a frog and returns 0.006
s later. If the speed of sound is 330 m/s, how far is the frog from the bat?
Ans. 0.99 m
A sonic measuring device registers a distance of 3.45 m
between the device and the
wall. If the speed of sound in the
room is 340 m/s, how long did the round trip of the
signal take?
Ans. 0.02 s
In an experiment, a tube is pulled out of water as a 550 Hz tuning fork rings over the open end. A resonance is heard. The tube is then pulled out a
distance of 0.30 m and the next resonance is heard. What is
the speed of sound in the tube? Ans. 330 m/s
Tuning fork A and B are the same
frequency. A small piece of putty is added to fork B.
What will happen to the frequency of tuning fork B?
A
B
Ans. decrease
The top two frequencies are played
and produce the beat
frequency shown in
red. What is the
difference in the top two frequencies
?1 s 2 s
Ans. 1 Hz
A light wave is shown below traveling to the right. The electric field part of the wave vibrates up-and-down. What type of wave is
a light wave?
Ans. transverse
Describe the motion of point 3 after the wave reflects from
the wall and moves toward the left.
Ans. Down-up-down, etc.
When looking at the light from a distant star, the light is shifted as the star moves in the circular path due to the gravity of the small unseen planet. Does the
star rotate clockwise or counterclockwise in the diagram below?
Ans. Counter-clockwise
If the speed of light is 3 x 108 m/s, how long does it take
light to travel from the Earth to the
Moon?
The distance between the Earth and the Moon is about
3 x 108 m.
Ans. 1 s
The hollow crest of the dinosaur acts as a pipe with both ends open. If the total
length of the chamber is 1.5 m and the creature produces a
standing wave in its 3rd harmonic, what is the frequency of sound
produced? Use vsound = 340 m/s Ans. 340 Hz
How does the wavelength of the reflected sound wave measuring
blood speed compare to the incident
sound wave?Ans. longer
Eight waves pass a point every 3 seconds. The
distance between crests is 2 m. What is the frequency of
the wave?
Ans. 8/3 Hz
Eight waves pass a point every 3 seconds. The
distance between crests is 2 m. What is the speed of the
wave?
Ans. 5.33 m/s
A 550 Hz tuning fork rings along with another fork (A) of unknown frequency. A beat with a frequency of 5 Hz is
heard. A third fork of frequency 540 Hz produces a beat frequency of 15 Hz when
ringing with A. What is the frequency of tuning fork A?
Ans. 555 Hz
The xylophone rings at its lowest frequency. What is the wavelength
at this lowest frequency?
20 cm Connecting
pointsAns. 80 cm
Waves on the Sun caused by the eruption of a solar flare. It traveled 1.3 x 107 m in one hour.
What was the speed of the wave (m/s)?
Ans. 3611 m/s