Answer:
we have to make another question we maxed it out again lol
Explanation:
Answer:
The alternative energy sources are defined as those resources that are used in place of the natural and non-renewable resources. This resources plays an important role in the conservation of natural resources.
The fossil fuels are the resources on which the people are directly dependent. Burning up of these fossils leads to the emission of carbon, which has a direct impact on earth. A small increase in the amount of carbon dioxide can lead to the increase in the surface temperature of earth.
In addition to this, these fossil fuels such as coal, petroleum, oil and natural gases are found to be present in a limited proportion, and it is a very expensive process to obtain these resources, so sustainable development method must be adopted in order to save this natural resources for the future generation.
Some of the examples of alternative resources that are widely used in place of fossil fuels are wind energy, solar energy, tidal energy, biomass energy and bio-fuels.
Thus, it is very important to develop and use alternative resources.
The crate moves at constant velocity, this means that its acceleration is zero, so the net force acting on the crate is zero (Newton's second law).
There are only two forces acting on the crate: the force F applied by the worker and the frictional force, acting in the opposite direction:

, where

is the coefficient of friction and

is the mass of the crate. Since the net force should be equal to zero, the two forces must have same magnitude, so we have:

And so, this is the force that the worker must apply to the crate.
Answer:
Gravitational Force.
Explanation:
Being one of the fundamental forces of nature, gravitational force is the weakest but has an infinite range. It is always attractive and acts between any two pieces of matter in nature.
Given:
The number of vibrations of the tuning fork is,

in,

To find:
The frequency of the fork
Explanation:
The frequency is the number of vibrations in 1 second
The frequency for the given fork is,

Hence, the frequency is 148 Hz.