Answer:
when the body is resting N = 246.96 N
when the body is resting on a tilted surface N = 212.12 N.
when the body is in a elevator N = 317.036 N
Explanation:
when the block is resting on a stationary surface the normal force is balanced by the weight of the body.
weight of the body = mg = 25.2×9.8 = 246.96 N
therefore normal force = 246.98 N.
when the block is resting on a tilted surface the normal force will be balanced by the 
component of the weight where Ф is the angle of inclination.
therefore N = mg
N= 212.12 N.
when the block is resting on a elevator that is accelerated upward the normal force will be the sum of weight and force due to acceleration ma
therefore N = 246.98 + 25.2×2.78
N = 317.036 N
I will assume here that the well is sufficiently short so that the time the sound takes to come from the bottom of the well to our ear is negligible.
Since the pebble moves by uniformly accelerated motion, the distance it covers is given by
where
is the gravitational acceleration
is the time the pebble takes to reach the bottom of the well
Therefore, the depth of the well is
and the correct answer is B.
So the people had to be. This equipment causes space
.Water
Adequate water supplies of high quality are necessary both for community use and local ecosystems. Communities and jurisdictions must work together to assure an adequate water supply to meet future needs. This section presents resources to aid in that effort.Energy
Communities require energy. Nonrenewable sources for power generation, home and workplace, and transportation cause pollution and its harmful impacts. Energy conservation and the use of renewable fuels provide cost-effective and more sustainable alternatives. This section contains resources available to make energy use more efficient.Air and Climate
Both the natural ecosystem and human health can be adversely impacted by declining air quality and climatic change. Communities can preserve air quality by limiting or eliminating the discharge of harmful chemicals into the air and by minimizing the sources of air pollution. This section contains resources and approaches that address air quality and climate change.Biodiversity
Biodiversity is particularly important for creating sustainability because of the specialized roles each species plays in maintaining ecological balance. Communities can promote healthy wildlife by supporting integrative approaches for managing, protecting, and enhancing wildlife populations and habitats appropriate to their area. Some examples are given here.Land, Forests, and Ecosystems
While providing a protective covering for soil, water, and the atmosphere, forests are also renewable sources of an endless variety of products. In a healthy ecosystem, policies and programs must balance economic and conservation needs. This section highlights cases where communities have developed land use practices and businesses that both conserve ecosystems and enhance local economies.
Answer:
346819 Pa or ,347000 Pa in 3 significant figures
Explanation:
P1= 325000Pa , T1= 283K ,
P2=? T1= 302 K
as here volume and mass both are constant so using ratio method for pressure temperature law we have P1/T1 = P2/T2
THIS WE CAN ALSO OBTAIN BY RATIO METHOD FOR GENERAL GAS LAW AS
P1V1/(m1T1 ) = P2 V2/ (m2 T2)
IF V1 = V2 =V AND m1=m2=m then expression reduces to
P1/T1 = P2/T2
or P2 = (P1/T1)×T2
P2 = (325000/283) × 302
P2 = 1148.41×302
P2=346819
P2 = 347000 Pa in 3 significant figures
