Answer:
Explanation:
The equation for this is
where f is the frequency, v is the velocity, and lambda is the wavelength. Filling in:
and
which means that
the wavelength is 1.37 m, rounded to the correct number of significant digits.
Answer:
Gravitational pull
Explanation:
There are four fundamental forces in nature:
- Gravitational force: it is an attractive force exerted between all objects having mass. Its magnitude is proportional to the product of the masses and inversely proportional to the square of the distance between the objects.
- Electromagnetic force: it is the force exerted between electrically charged object. It can be either attractive ore repulsive. Its magnitude is proportional to the product of the charges and inversely proportional to the square of the distance between the objects.
- Strong nuclear force: it is the force responsible for holding protons and neutrons together in the nuclei of the atoms. It is attractive and acts only on a very short scale.
- Weak nuclear force: it is the force responsible for certain nuclear decay processes (radioactivity).
In this problem, landslides occur when certain masses of terrain are attracted towards the ground - they are attracted because of the gravitational force.
So, the correct answer is
gravitational pull
I think they decrease echo and reduce noise, they do this by either absorbing vibrations or by scattering the sound so that echoes arrive at different times rather than reverberating as a standing wave. An echo is a reflection of a sound that arrives at the listener with a delay after the direct sound. The delay is usually proportional to the distance of the reflecting surface from the source and the listener.
Answer:
The main use for gypsum is in the production of Plaster of Paris and drywall products. Gypsum is also used as a soil conditioner.
Explanation:
Answer:
The half-life is 
Explanation:
Using the decay equation we have:
Where:
- λ is the decay constant
- A(0) the initial activity
- A is the activity at time t
We know the activity decrease by a factor of two in a one hour period (t = 1 h), it means that 
Taking the natural logarithm on each side we have:
Now, the relationship between the decay constant λ and the half-life t(1/2) is:
I hope it helps you!
