Answer:
434 Hz
Explanation:
According to the Doppler effect, when a source of a wave is moving towards an observer at rest, then the observer will observe an apparent frequency which is higher than the original frequency of the source.
In this situation, Tina is driving towards Rita. Tina is the source of the sound wave (the horn), while RIta is the observer. Since the original frequency of the sound is 400 Hz, Rita will hear a sound with a frequency higher than this value.
The only choice which is higher than 400 Hz is 434 Hz, so this is the frequency that Rita will hear.
Answer:
No. Twice as much work will give the ball twice as much kinetic energy. But since KE is proportional to the speed squared, the speed will be 
times larger.
Explanation:
The work done on the ball is equal to the kinetic energy gained by the ball:
So when the work done doubles, the kinetic energy doubles as well:
However, the kinetic energy is given by
where
m is the mass of the ball
v is its speed
We see that the kinetic energy is proportional to the square of the speed, 
. We can rewrite the last equation as
which also means
If the work is doubled,
So the new speed is
So, the speed is 
times larger.
Answer:
Thumb
Explanation:
The direction of the magnetic field can be determined by using the right-hand rule. According to this rule, hold a current carrying wire in your right hand such that the thumb of the right-hand point in the direction of electric current. The curled finger gives the direction of the magnetic field.
Hence, the thumb shows the electric current.
Explanation:
1. Low-energy particle detector: This particle detector measures the charged particles of the solar winds.
2. Magnetometer boom: This device measures magnetic fields produced by astronomical bodies.
3. High-gain antenna: A HGA has a narrow radio beam that is used to enhance the strength of signal. They simply amplify the weak signals.
4. Photopolarimeter: This is an instrument that is used to measure the strength and intensity and polarization of reflected light.
Answer:
13.7m
Explanation:
Since there's no external force acting on the astronaut or the satellite, the momentum must be conserved before and after the push. Since both are at rest before, momentum is 0.
After the push
Where 
is the mass of the astronaut, 
is the mass of the satellite, 
is the speed of the satellite. We can calculate the speed 
of the astronaut:
So the astronaut has a opposite direction with the satellite motion, which is further away from the shuttle. Since it takes 7.5 s for the astronaut to make contact with the shuttle, the distance would be
d = vt = 1.83 * 7.5 = 13.7 m
