List the producers,consumers,and decomposers in food web

The theory of biological evolution is generally accepted by the modern scientific community as true: True or False?

gayaneshka [121]

True, the accepted modern theory of life is biological evolution.

4 0

2 years ago

A 12,500 N alien UFO is hovering about the surface of Earth. At time , its position can be given as () = ((0.24 m/s^3)^3 + 25 m)

stepladder [879]

a) $F=(3675i-4543k)N$

b) 5843 N

Explanation:

a)

The position of the UFO at time t is given by the vector:

$r(t)=(0.24t^3+25)i+(4.2t)j+(-0.43t^3+0.8t^2)k$

Therefore it has 3 components:

$r_x=0.24t^3+25\\r_y=4.2t\\r_z=-0.43t^3+0.8t^2$

We start by finding the velocity of the UFO, which is given by the derivative of the position:

$v_x=r'_x=\frac{d}{dt}(0.24t^3+25)=3\cdot 0.24t^2=0.72t^2\\v_y=r'_y=\frac{d}{dt}(4.2t)=4.2\\v_x=r'_z=\frac{d}{dt}(-0.43t^3+0.8t^2)=-1.29t^2+1.6t$

And then, by differentiating again, we find the acceleration:

$a_x=v'_x=\frac{d}{dt}(0.72t^2)=1.44t\\a_y=v'_y=\frac{d}{dt}(4.2)=0\\a_z=v'_z=\frac{d}{dt}(-1.29t^2+1.6t)=-2.58t+1.6$

The weight of the UFO is W = 12,500 N, so its mass is:

$m=\frac{W}{g}=\frac{12500}{9.8}=1276 kg$

Therefore, the components of the force on the UFO are given by Newton's second law:

$F=ma$

So, Substituting t = 2 s, we find:

$F_x=ma_x=(1276)(1.44t)=(1276)(1.44)(2)=3675 N\\F_y=ma_y=0\\F_z=ma_z=(1276)(-2.58t+1.6)=(1276)(-2.58(2)+1.6)=-4543 N$

So the net force on the UFO at t = 2 s is

$F=(3675i-4543k)N$

b)

The magnitude of a 3-dimensional vector is given by

$|v|=\sqrt{v_x^2+v_y^2+v_z^2}$

where

$v_x,v_y,v_z$ are the three components of the vector

In this problem, the three components of the net force are:

$F_x=3675 N\\F_y=0\\F_z=-4543 N$

Therefore, substituting into the equation, we find the magnitude of the net force:

$|F|=\sqrt{3675^2+0^2+(-4543)^2}=5843 N$

7 0

2 years ago

The basketball coach tells his team to run sprints back and forth across the court, which is 30 m long. They start at the left e

sp2606 [1]

Distance is the total length of an object's path. Displacement is the overall change in position, ie. how far an object is from its initial position.

The court is 30 m long, so a path going back and forth once is 60 m long. Going along this path 6 times totals 360 m.

The end point is the same as the starting point, so the displacement is 0 m.

5 0

3 years ago

Mariah trained for months leading up to the marathon, and she won. After seeing this, her friends and family would describe her

alexandr402 [8]

Answer:

Mariah trained for months leading up to the marathon and won. Her sole motivation was that after seeing her winning the marathon, her friends and family would call her as motivated and athletic. It means that Mariah wanted to fulfill her esteem needs.

Explanation:

According to Abraham Maslow:

Safety needs includes the personal security, the safety of health, resources and property. etc.

Physiological needs falls at the lowest level of basic needs. It includes food, water, rest. etc which are necessary for an individual's survival.

Esteem includes the need of respect and self-confidence.

Cognitive needs includes the desire of knowledge, to know things, to know what is happening and why is it happening around you.

In Mariah's case, she needed respect and motivation and thus she was trying to fulfill her esteem needs by winning the marathon.

8 0

3 years ago

Read 2 more answers

How do the wavelengths of electromagnetic energy absorbed by materials on earth compare?

Dmitrij [34]

Explanation:

The shorter wavelength electromagnetic waves from sun are absorbed by earth material in form of short wavelength and the radiated wavelength are longer ones. Also higher energy waves are of shorter wavelength and lower energy waves have longer wavelength. So, they are absorbed as short wavelength and radiated back as long wavelength.

8 0

3 years ago