1. 168.1 Hz
To find the apparent frequency heard by the driver in the car, we can use the formula for the Doppler effect:
where
f is the original sound of the horn
v is the speed of sound
is the velocity of the observer (the driver and the car), which is positive if the observer is moving towards the source and negative if it is moving away
is the velocity of the sound source (the train), which is positive if the source is moving away from the observer and negative otherwise
In this problem we have, according to the sign convention used:
Substituting, we find:
2. 
The speed of light can be calculated as
where
d is the distance travelled
t is the time taken
In this problem:
is the total distance travelled by the laser beam (twice the distance between the Earth and the Moon)
t = 2.60 s is the time taken
Substituting in the formula,
Nitrogen
Explanation:
Adding one proton to a carbon atom makes Nitrogen.
A quick introspection on atoms:
- An atom is made up of three fundamental particles.
- They are protons, neutrons and electrons.
- The protons are positively charged and the neutrons do not carry any charges.
- Electrons are negatively charged.
The difference between an atom and another is the number of protons in them. This is the atomic number.
The periodic table of element is a list of elements arranged based on the number of protons they have. Every element on the table has unique number of protons which makes it differ from another.
- Atoms do not readily lose their protons because they are held by nuclear forces in the nucleus of an atom.
When an element gains a proton, it becomes another element.
Carbon has proton number of 6
If a proton is added to it, it becomes 7
This is the proton or atomic number of nitrogen.
Learn more:
Atomic number brainly.com/question/5425825
#learnwithBrainly
Answer:
rad
Explanation:
∅ = 
= 
∅ = rad
The minimum resolvable angle = rad
<span> Using conservation of energy
Potential Energy (Before) = Kinetic Energy (After)
mgh = 0.5mv^2
divide both sides by m
gh = 0.5v^2
h = (0.5V^2)/g
h = (0.5*2.2^2)/9.81
h = 0.25m
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