Answer:
The particle’s velocity is -16.9 m/s.
Explanation:
Given that,
Initial velocity of particle in negative x direction= 4.91 m/s
Time = 12.9 s
Final velocity of particle in positive x direction= 7.12 m/s
Before 12.4 sec,
Velocity of particle in negative x direction= 5.32 m/s
We need to calculate the acceleration
Using equation of motion
Where, v = final velocity
u = initial velocity
t = time
Put the value into the equation
We need to calculate the initial speed of the particle
Using equation of motion again
Put the value into the formula
Hence, The particle’s velocity is -16.9 m/s.
1)a 2)D 3)a. I think the answers are
16/9 m/s^2
negative 4/3 m/s^2
14 m/s
the last one is too detailed to do in my head while on the bus; sorry
Answer:
The correct answer is B.
The astronaut will know due to the light from the explosion.
Explanation:
Sound and vibrations require a medium such as air to travel through. Space, there is no air. Only a vacuum. So sound and vibrations are unable to travel. Light requires no medium to travel. It can go through a vacuum.
Therefore the Astronaut will see a bright flash of light as it travels from the explosion to outer space. It is also important to note that light can travel very far because nothing else interacts with its wave particles and as such, it cannot be impeded.
Cheers!
The concept required to solve this problem is related to the wavelength.
The wavelength can be defined as the distance between two positive crests of a wave.
The waves are in phase, then the first distance is
And out of the phase when
Thus the wavelength is
Here,
Wavelength
If we rearrange the equation to find it, we will have
Therefore the wavelength of the sound is 20cm.
