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2 years ago

What should you avoid doing to ensure your farming practises were sustainable?

1 answer:

7 0

Sustainable crops are grown in a different manner from industrial crops. Sustainable crop farmers focus on ensuring that their farming practices can be sustained over time and do not cause undue damage to the environment.

•Minimal to No Pesticide Use
•Limit Environmental Damage
•Focus on Soil Health
•Sustainable Seed and Plant Varieties
(More in website beneath)
Further Info/ Source: http://www.sustainabletable.org/249/sustainable-crop-production

You might be interested in

At what position or positions on the x-axis is the electric field zero?

ElenaW [278]

Answer:

The electric field will be zero at x = ± ∞.

Explanation:

Suppose, A -2.0 nC charge and a +2.0 nC charge are located on the x-axis at x = -1.0 cm and x = +1.0 cm respectively.

We know that,

The electric field is

$E=\dfrac{kq}{r^2}$

The electric field vector due to charge one

$\vec{E_{1}}=\dfrac{kq_{1}}{r_{1}^2}(\hat{x})$

The electric field vector due to charge second

$\vec{E_{2}}=\dfrac{kq_{2}}{r_{2}^2}(-\hat{x})$

We need to calculate the electric field

Using formula of net electric field

$\vec{E}=\vec{E_{1}}+\vec{E_{2}}$

$\vec{E_{1}}+\vec{E_{2}}=0$

Put the value into the formula

$\dfrac{kq_{1}}{r_{1}^2}(\hat{x})+\dfrac{kq_{2}}{r_{2}^2}(-\hat{x})=0$

$\dfrac{kq_{1}}{r_{1}^2}(\hat{x})=\dfrac{kq_{2}}{r_{2}^2}(\hat{x})$

$(\dfrac{r_{2}}{r_{1}})^2=\dfrac{q_{2}}{q_{1}}$

$\dfrac{r_{2}}{r_{1}}=\sqrt{\dfrac{q_{2}}{q_{1}}}$

Put the value into the formula

$\dfrac{2.0+x}{x}=\pm\sqrt{\dfrac{2.0}{2.0}}$

$2.0+x=x$

If x = ∞, then the equation is be satisfied.

Hence, The electric field will be zero at x = ± ∞.

4 0

2 years ago

How do you express 78,000 in scientific notation?

White raven [17]

The Answer is= 7.8 x 10^4

7 0

2 years ago

3. Maverick and Goose are flying a training mission in their F-14. They are

Elanso [62]

Answer:

A. The bomb will take <em>17.5 seconds </em>to hit the ground

B. The bomb will land <em>12040 meters </em>on the ground ahead from where they released it

Explanation:

Maverick and Goose are flying at an initial height of $y_0=1500m$ , and their speed is v=688 m/s

When they release the bomb, it will initially have the same height and speed as the plane. Then it will describe a free fall horizontal movement

The equation for the height y with respect to ground in a horizontal movement (no friction) is

$y=y_0 - \frac{gt^2}{2}$ [1]

With g equal to the acceleration of gravity of our planet and t the time measured with respect to the moment the bomb was released

The height will be zero when the bomb lands on ground, so if we set y=0 we can find the flight time

The range (horizontal displacement) of the bomb x is

$x = v.t$ [2]

Since the bomb won't have any friction, its horizontal component of the speed won't change. We need to find t from the equation [1] and replace it in equation [2]:

Setting y=0 and isolating t we get

$t=\sqrt{\frac{2y_0}{g}}$

Since we have $y_0=1500m$

$t=\sqrt{\frac{2(1500)}{9.8}}$

$t=17.5 sec$

Replacing in [2]

$x = 688\ m/sec \ (17.5sec)$

$x = 12040\ m$

A. The bomb will take 17.5 seconds to hit the ground

B. The bomb will land 12040 meters on the ground ahead from where they released it

6 0

2 years ago

This chart lists four examples of two objects that are in contact.

Oxana [17]

Before coming into conclusion first we have to understand the direction of heat flow.

Heat is the transferred thermal energy from one body to another body due to the temperature difference just like water flows from higher level to lower level.

Whenever two bodies having different temperature come closer to each other heat will flow from hotter body to cooler one if no external work is done. The heat flow may be through any of the ways i.e conduction,radiation or convection. Hence temperature difference is the parameter which gives the direction of heat flow.

The temperature is also considered as a measure of average kinetic energy of the substance.The thermal energy does not give the direction heat flow. Heat may flow from the body having low thermal energy but at higher temperature to the body having higher thermal energy but at low temperature. The reverse does not happen naturally .

In example 1 there is fire and air. Obviously fire is at high temperature and air at low temperature.So heat will flow from object 1 to object 2.

In example 2 there is a metal at 80 degree Celsius and another metal at 12 degree Celsius .So heat will flow from object 1 to object 2

In example 3 we have cooler ocean and warm air. So the heat will flow from object 2 to object 1.

In example 4 we have a tool with high thermal energy and a material with little thermal energy.We already know that thermal energy can not determine the direction of heat flow. Here the temperature of each substance is not given.The kinetic energy is part of thermal energy.So there is the chance of higher kinetic energy of the tool for having higher thermal energy .At that time the heat will flow object 1 to object 2.Otherwise the reverse will occur. So it is a special case.

As per the question only option 4 is correct which tells that heat will flow from object 1 to object 2 in examples 1,2,4, and heat will flow from object 2 to 1 in example 3. Other options violate the fundamental law of thermodynamics.

7 0

2 years ago

Scientific work is currently underway to determine whether weak oscillating magnetic fields can affect human health. For example

ValentinkaMS [17]

Answer:

$2.02672\times 10^{-11}\ V$

Explanation:

f = Frequency = 75 Hz

B = Magnetic field = $1\times 10^{-3}\ T$

d = Diameter of cell = $7.4\ \mu m$

t = Time taken

$\omega$ = Angular frequency

The expression of emf is

$E=NAB\omega sin\omega t$

Emf is maximum when $sin\omega t=1$ and N = number of turns = 1

$E_m=AB\omega\\\Rightarrow E_m=\pi \left(\frac{d}{2}\right)^2 \times B \times 2\pi\times f\\\Rightarrow E_m=\pi \left(\frac{7.4\times 10^{-6}}{2}\right)^2\times 1\times 10^{-3}\times 2\pi\times 75\\\Rightarrow E_m=2.02672\times 10^{-11}\ V$

The maximum emf that can be generated around the perimeter of a cell in this field is $2.02672\times 10^{-11}\ V$

4 0

2 years ago