What is the net force EF?

Answer:

29.41%

Explanation:

Given that,

In 1630 at the beginning of European settlement, about 425,000,000 hectares of the United States were covered with trees.

By 2017, the area covered by trees was reduced to 300,000,000 hectares.

We need to find the percentage decrease in the area covered by trees between 1630 and 2017.

The percentage decrease in any value is given by :

[tex]\%=\dfrac{300,000,000 -425,000,000 }{425,000,000 }\times 100\\\\=29.41\%[/tex]

So, the percentage decrease in the area covered by the trees is 29.41%.

Answer:

k. e. = 1/2 mv^2

1/2 * 1000 * (5)^2

1/2 * 1000 * 25

12500 joules

k. e. = 1/2 mv^2

1/2 * 1000 * (10)^2

1/2 * 1000 * 100

50000

change in k. e. = final - initial

50000 - 12500

= 37500 joules

hope it helps you

Answer:

Change in the magnetic field

Explanation:

The refraction index of water (1.33) is higher than air (1), therefore the light ray will bend towards the normal.

Answer:  Distance is a scalar quantity and direction is not applicable.  We can use graphs to depict an object's change in position over time.  Create a large number line in the classroom by taping index cards on the floor or wall 1 meter apart.

Explanation: I really hope that was helpful.

Answer:

Solution in photo

Explanation:

A car moves around in a circular racing track, and it takes 120 seconds to do a lap of 8 km, so the speed in km/hr is 239.76 km/hr.

The speed of an object, commonly known as v in mechanics, is a scalar quantity that corresponds towards the size of the change in that object's position over duration or the size of the change in that object's position per unit of time.

The instantaneous velocity is the absolute maximum of the average speed as the time interval's duration gets closer to zero. The cruising pace of an object in a time interval is calculated by dividing its distance traveled by the time interval's duration. Velocity and speed are different concepts.

The given data according to the question is,

Time, t = 120 s

Distance, d = 8 km

s = 8/120

s =0.0666 km/sec or

s = 0.0666/1s × 3600

s = 239.76 km/hr.

Therefore, the speed is 239.76 km/hr.

To know more about Speed:

https://brainly.com/question/312131

#SPJ2

Explanation:

1. Force is something that pushes or pulls you

2. The 150 lbs person accelerated faster because they had less force pushing or pulling them down.

Answer:

QESARDFRGTSRTATFREVERSRvrvqwqv

Explanation:

vfqfvcafbraf w rfdsd AEWvd a

Answer:

Speed is the time rate at which an object is moving along a path, while velocity is the rate and direction of an object's movement. Put another way, speed is a scalar value, while velocity is a vector.

Explanation:

Answer:

14.8J

Explanation:

PE=MGH

M=0.21

G=9.8m/s

H= 7.2 m

0.21x7.2x9.8= 14.8176 J

Answer:

(i) It was the first such model was supported by scientific evidence: FALSE

(ii) It was not published until Copernicus was close to death: TRUE

(iii) It was the first time a heliocentric model had ever been suggested: FALSE

(iv) It was not controversial, and was readily accepted: FALSE

(v) It stated that the Sun revolved around the Earth: FALSE

(vi) It stated that the Earth revolved around the Sun: TRUE

Explanation:

We proceed to demonstrate the validity of each option from statement:

(i) It was the first such model was supported by scientific evidence: FALSE

The geocentric model was based mostly on interpretation of two astronomical findings: (a) The displacement of the stars with respect to Earth due to stellar parallax, (b) The apparent consistency of brightness of the planet Venus seen from Earth.

(ii) It was not published until Copernicus was close to death: TRUE

Copernicus published his heliocentric theory, contained in the book De revolutionibus orbium coelestium, months before his death, in 1543.

(iii) It was the first time a heliocentric model had ever been suggested: FALSE

Greek mathematician and astronomer Aristarchus of Samos was the first person who proposed the heliocentric model in the 4th Century.

(iv) It was not controversial, and was readily accepted: FALSE

The Roman Catholic Church defended geocentric model proposed by Claudius Ptolemy and Tycho Brahe and rejected the model proposed by Copernicus, whose publication was included in the Index Librorum Prohibitorum in 1616.

(v) It stated that the Sun revolved around the Earth: FALSE

This is the main idea of the geocentric model.

(vi) It stated that the Earth revolved around the Sun: TRUE

This is the main idea of the heliocentric model.

Answer:

7660 m/s

Explanation:

multiply 110304 x 1000 to turn it into meters then turn 4 hours into seconds making it 14400 seconds. Then divide 11030400 by 14400

Answer:

.

Explanation:

Explanation:

Given parameters:

Number of cycles  = 10cycles

Time taken  = 50s

Unknown:

Period of its rotation  = ?

Frequency of its rotation  = ?

Solution:

The period of rotation is the time taken time taken for a body to complete a number of rotation;

 Period  = [tex]\frac{t}{n}[/tex]  

t is the time

n is the number of cycles

 Period  = [tex]\frac{50}{10}[/tex]  = 5s

The period is 5s

Now, frequency is the inverse of period;

   F = [tex]\frac{1}{period}[/tex]  = [tex]\frac{1}{5}[/tex]   = 0.2Hz

Answer:

heyyy

May I Know the full question

Answer:

Answer: 0.83333333333 km/h

Explanation: give brainliest

Answer:

I think ur wrong to say force doesn't change an object velocity

Explanation:

Force affects how objects move. They change the direction of motion of an object that is already moving. Since force causes a change in the speed or direction of an object, we may say that force causes changes in an object velocity.

Answer:

A: Air pressure decreases as air density increases

Explanation:

Pressure is a force exerted on or against an object by being in contact with a substance. Thus, air pressure is due to the bombardment of the air (gas) particles with a surface. Density is defined as the mass per volume of a substance. Thus, air density is defined as the mass of air per unit volume.

If that Explanation does not make any sense let me make it easier.

The air at the top of a mountain is cooler than the air at the bottom. This temperature difference is due to a phenomenon that occurs in Earth’s atmosphere. Air rises and sinks based on differences in temperature and pressure. Here’s a quick experiment that will help explain the role of pressure.Take in a deep breath as if you were ready to blow out birthday candles. Puff your cheeks with air like a chipmunk. Hold it for a few seconds, and then blow the air slowly from your cheeks.Cold air sinks while warm air rises because cold air is denser than warm air. When a lot of cold air sinks, it creates an area of high air pressure where it hits the surface. This high-pressure air flows to an area of low pressure, creating wind. When this air warms, it rises up into the atmosphere.Temperature decreases as altitude increases. That’s why a mountain peak may be covered with snow while the bottom of the mountain is full of green plants and trees. When warm air rises into the atmosphere, it cools. The density of the air increases as it cools, which eventually creates an area of high pressure and starts the cycle again.

If not for this phenomenon of air rising and sinking in the atmosphere, there would be no wind or weather.

I hope that helped!

The normal force felt by the box has magnitude

F[normal] = (1 kg) g = 9.8 N

so that the maximum magnitude of static friction is

F[s. friction] = 0.8 F[normal] = 7.84 N

In order to get the box to move, (C) a minimum force of 7.84 N is required.

Answer:

6.56168

Explanation:

Answer:

without oxygen because

Answer:

Without oxygen

Explanation:

Answer:

I believe D

Explanation:

I'm not for sure but I think it is D

Answer:

3000W

Explanation:

Given parameter:

Weight of safe  = 2000N

Height of lift = 6m

Time = 4s

Unknown:

Power used by Rudolph = ?

Solution:

Power is the rate at which work is being done. It is expressed as:

 Power  = [tex]\frac{Work done }{Time taken}[/tex]  

   Work done  = Weight x height = 2000 x 6  = 12000J

Power  = [tex]\frac{12000}{4}[/tex]   = 3000W

Answer:

Nothin will move, it will stay the same since no force is greater than the other. it's "the same amount of force" which also means an equal amount of force

Explanation:

The forces are only equal if there is no acceleration (which in the game of tug of war, accelerating yourself and your opponent is the idea). If the force on the rope and the ground are both equal either nothing moves or some other force is being applied in the system.

Hope this helped!

Answer:

have two or more paths

Explanation:

A parallel circuit is one that has two or more paths for the electricity to flow, the loads are parallel to each other.

Answer:

there should some picture to identify right?

pls edit your question and insert the picture..

Answer:

Well it depends Because An axe Would be A Simple machine well as a drill is

Answer:

Disagree

Explanation:

We cannot see infared lights.

Answer:

Explanation:

b )

Normal force R = mgcosθ

= 76.6 x 9.8 x cos 38

R = 591.5 N

c )

Force of friction

= μ R

μ is coefficient of friction .

= .15 x 591.5

= 88.73 N

d )

Net force

= mg sinθ - friction

= 76.6 x 9.8 x sin 38 - 88.73

= 462.16 - 88.73

= 373.43 N

Acceleration = 373.43 / 76.6

a = 4.87 m / s²

e )

v² = u² + 2 a s

s = 40.5 m

a = 4.87

u = 0

v² = 0 +2 x 4.87 x 40.5

= 394.5

v = 19.86 m /s

f )

v = u + a t

19.86 = 0 + 4.87 t

t = 4 .07 s

Answer:

They are reflected.

Explanation:

Red light is absorbed while green light is reflected, causing the color to be green in human eyes.

Answer:

C

Explanation: