4. A car accelerates uniformly from rest at 3.2 m/s^.

A bicyclist is traveling at a speed of 20.0 m/s as he approaches the bottom of a hill. He decides to coast up the hill and stops

Rudiy27

Answer:

Vertical height of the hill, h = 20.4 meters

Explanation:

Given that,

Speed of the bicyclist, v = 20 m/s

To find,

The vertical height of the hill.

Solution,

Let h is the height of the hill. When he approaches the bottom of the hill, the loss in kinetic energy is equal to the gain in potential energy. Using the conservation of energy as,

$\dfrac{1}{2}mv^2=mgh$

$h=\dfrac{v^2}{2g}$

$h=\dfrac{(20)^2}{2\times 9.8}$

h = 20.4 meters

Therefore, the vertical height of the hill is 20.4 meters. Hence, this is the required solution.

5 0

3 years ago

A major artery with a 1.7 cm2 cross-sectional area branches into 18 smaller arteries, each with an average cross-sectional area

Alex

Answer:

0.14

Explanation:

Flow rate is the volume flowing through a point at a particular time, in calcuing flow rate we have

Q= v*t

it in terms of Area, we have Q= A*v

Where A= area

v= velocity.

Solving the question , flow rate is constant then

A*v= constant

A(i) v(i)= A(f) v(f)

Where A(i)= initial area= 1.00cm^2

A(f)= final area= 0.400cm^2

V(i) and V(f) are the initial and final velocity respectively and the ratio of the two will gives us the factor

Substitute the values into the equation we have

1 V(i)= 4 V(f)

But we were told that the cross sectional area of 1.00cm^2 branches into 18 smaller arteries.

Then

1 V(i)=0.4 V(f)*(18)

1 V(i)=7.2V(f)

Then if we find the ratio of the velocity, we will get the factor.

V(f)/V(i)= 1/7.2

V(f)/V(i)=0.14

Hence, the factor of the average velocity of the blood reduced when it passes into these branches is 0.14

8 0

3 years ago

An airplane flies 700 miles with a tail wind in 2.0 hrs. If it takes 2.5 hrs to cover the same distance against the headwind, th

nikklg [1K]

Answer:

B).315mph

Explanation:

Let the speed of the plane = p

Let the speed of the wind = w

Set up the system equation as;

Relative V: Time: Distance:

in wind direction: p + w 2 700

against wind: p - w 2.5 700

2(p + w) = 700

2.5(p - w) = 700

2p + 2w = 700

2.5p - 2.5w = 700

2.5 x: 5p + 5w = 1750

2 x: 5p - 5w = 1400

10p = 3150

p = 315 mph

Therefore, he speed of the plane in still air is 315 mph

6 0

4 years ago

I need help with this answer

ololo11 [35]

The answer is Synthesis

7 0

3 years ago

Select. The star cycle that is accurate

melomori [17]

One stellar-mass star, red giants, white dwarfs, or planetary nebulae will make up the correct star cycle. Option C is correct.

<h3 /><h3>What is the solar system?</h3>

The satellites of the planet, countless comets, asteroids, and meteoroids, as well as the interplanetary medium, make up the solar system.

The complete question is;

"Choose the correct star life cycle.

A. Supernova, star as well as red giant, the nebula is incorrect.

B. Nebula, white dwarf, planetary nebula That is incorrect.

C. Planetary nebula, red giant, white dwarf, and star with a single stellar mass That is true!

D. Nebula, a star of one stellar mass, is not correct. It is correct if the star had four or more stellar masses."

Star of one stellar mass, red giant, white dwarf, and planetary nebula make up the proper life cycle.

Hence option C is correct.

To learn more about the solar system refer to the link;

brainly.com/question/1207587

#SPJ1

5 0

2 years ago