Answer: V = 15 m/s
Explanation:
As stationary speed gun emits a microwave beam at 2.10*10^10Hz. It reflects off a car and returns 1030 Hz higher. The observed frequency the car will be experiencing will be addition of the two frequency. That is,
F = 2.1 × 10^10 + 1030 = 2.100000103×10^10Hz
Using doppler effect formula
F = C/ ( C - V) × f
Where
F = observed frequency
f = source frequency
C = speed of light = 3×10^8
V = speed of the car
Substitute all the parameters into the formula
2.100000103×10^10 = 3×10^8/(3×10^8 -V) × 2.1×10^10
2.100000103×10^10/2.1×10^10 = 3×108/(3×10^8 - V)
1.000000049 = 3×10^8/(3×10^8 - V)
Cross multiply
300000014.7 - 1.000000049V = 3×10^8
Collect the like terms
1.000000049V = 14.71429
Make V the subject of formula
V = 14.71429/1.000000049
V = 14.7 m/s
The speed of the car is 15 m/s approximately
Answer:
Technique of comparing abundance ratio between radioactive isotopes to a reference isotope to determine the age of a material called radioactive dating. It determines the age by having a more abundance of isotopes in the cellular being.
Answer electrons are negative. Protons are positive, and neutrons are neutral
Answer:
By Applying pressure to the brakes
Explanation:
Driving cars through deep water that is more than 10cm can make the cars to float. Most modern cars are usually water- tight so they can start to float through water that is about 30cm deep, fast moving water is very powerful so one needs to be very careful when driving.
If the brakes are wet test them by pressing or tapping on them gently.
You can as well dry brakes by driving in low gear and applying pressure to the brakes.
Question:
What two forces are balanced in what we call gravitational equilibrium?
A) the electromagnetic force and gravity
B) outward pressure and the strong force
C) outward pressure and inward gravity
D) the strong force and gravity
E) the strong force and kinetic energy
Answer:
The correct answer is C) Outward Pressure and Inward gravity
Explanation:
Gravitational equilibrium is a balance between the inward pull of gravity and the outward push of internal gas pressure. It also refers to the condition of a star in which the weight of overlying layers at each point is balanced by the total pressure at that point.
As the weight increases in the lower layers of the sun, the pressure also increases to maintain this balance. So you find that the outward push of pressure balances the inward pull of gravity thus creating an equilibrium.
Why is gravitational equilibrium important?
The simple answer is <u>balance. </u> If for instance the sun as a stable star (which has gravitational equilibrium) loses it's balance, it becomes highly unstable and prone to violent outbursts. These outbursts are caused by the very high radiation pressure at the star's upper layers, which blows significant portions of the matter at the "surface" into space during eruptions that may rage for several years. Of course such a condition is adverse to the existence and support of life.
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