A bicyclist in the Tour de France crests a mountain pass as he moves at 15 km/h. At the bottom, 4.2 km farther, his speed is 65 km/h. Estimate his average acceleration while riding down the mountain.

Answers

Answer 1

Answer: 18 km/hr*1000m/km*1 hr/3600 sec= 5 m/sec

85 km/hr= 23.6 m/s

distance = 4000m

distance= initial distance+initial velocity*time+ 1/2 acceleration*time^2

initial distance=0

4000= 5.0*t+ 1/2 (accel)(time)^2

Velocity=initial velocity+ acceleration * time

23.6 m/s= 5.0 m/s+ acceleration * time

We now have two equations and two unknowns. Solve them and you have your answer.

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The kinetic energy of all the particles in a given sample of matter is the same.a. True b. False

Average amount of time wind machines operate

Answers

The wind machine on an average operates for a time of about $\boxed{3-4\text{ hours}}$ .

Explanation:

The wind energy is the method of using the energy carried by the wind to generate the power. The wind energy is the considered as the conventional and clean source of energy.

The wind machines require the high power winds to rotate the blades of the windmill and produce power using the energy of the moving wind.

The winds blow at such high speed for a very small time during the day, the wind machine cannot be expected to work for a longer time during the whole day.

The wind energy can be obtained form a wind mill for a limited time unlike the other form of energy like thermal energy or even the solar energy. The thermal energy can be obtained at anytime due to burning of fuel whereas the solar energy can at least be obtained during the whole day time.

Thus, the wind machine on an average operates for a time of about $\boxed{3-4\text{ hours}}$ .

Learn More:

1. Acceleration of the box under friction brainly.com/question/7031524

2. The kinetic energy of an object depends on the brainly.com/question/137098

3. The approximate time taken to walk for 2000 miles brainly.com/question/3785992

Answer Details:

Grade: Middle School

Subject: Physics

Chapter: Energy

Keywords:

wind energy, conventional source, energy, thermal, solar, 3-4 hours, high speed, machine, time, operate.

The potential energy of a 25 kg bicycle resting at the top of a 3 m high hill is _______ J

Answers

The potential energy:
E p = m · g · h
m = 25 kg, g = 9.81 m/s², h = 3 m
E p = 25 kg · 9.81 m/s² · 3 m = 735.75 J

Hello!

The potential energy of a 25 kg bicycle resting at the top of a 3 m high hill is _______ J

If: 1 Joule = 1 kg.m²/s²

We have the following data:

GPE (Gravitational Potential Energy) = ? (in J)

m (mass) = 25 kg

g (gravity) ≈ 9.81 m/s²

h (height) = 3 m

We apply the data to the formula of the gravitational potential energy, we have:

$GPE = m*g*h$

$GPE = 25\:kg*9.81\:(m)/(s^2) *3m$

$GPE = 735.75\:kg*(m^2)/(s^2)$

$\boxed{\boxed{GPE = 735.75\:J}}\:\:\:\:\:\:\bf\green{\checkmark}$

Answer:

735.75 J

________________________

$\bf\green{I\:Hope\:this\:helps,\:greetings ...\:Dexteright02!}\:\:\ddot{\smile}$

A person looks at a gem stone using a converging lens with a focal length of 12.5 cm. The lens forms a virtual image 30.0 cm from the lens. Determine the magnification. Is the image upright or inverted?

Answers

THE MAGNIFICATION FROM THE GEMSTONE WILL HAVE 3.4 MAGNIFICATION. THE IMAGE WILL BE PRODUCE UPRIGHT.

Explanation:

WE WILL USE FORMULA ,

$(1)/(f)$ = $(1)/(p) + (1)/(q)$

where q = -30.0 cm

f = 12.5 cm

so, $p =(1)/(f)-(1)/(q)$ )⁻¹

$=(1)/(12.5cm)-(1)/(-30 cm)$ )⁻¹

= 8.82353 cm

m= $(-q)/(p)$

= $-((-30)/(8.82353))$

m= 3.4

so the magnification will be 3.4 which is upright image as magnification is positive.

As a person looks at gem stone using converging lens with focal length of 12.5 cm and virtual image 30 cm from lens the magnification for such will be 3.4 .And the image will be upright.

Final answer:

For the case of a gem being observed through a converging lens, creating a virtual image located from the lens, the magnification would be greater than 1 and positive, suggesting an upright and magnified image.

Explanation:

In the given scenario, the gem stone is being observed through a converging lens with a focal length of 12.5 cm, and a virtual image is forming 30.0 cm from the lens. To find the magnification, which is a measure of how much larger or smaller the image is relative to the object, we use the formula for magnification in lens theory: Magnification (m) = - Image Distance (di) / Object Distance (do). Since we're dealing with a virtual image, the image distance is a negative value (-30.0 cm).

However, we are not given the object distance (do). In the context of magnifiers and conjugate rays, and taking into account that our image is virtual, we can assume that the value of the object distance (do) is less than the value of the focal length (12.5 cm) for this so-called 'Case 2' image. Therefore, we can say that the magnification (m) is greater than 1 and positive, which indicates that the image of the gem stone is upright and magnified (larger than the object).

Learn more about Lens Theory here:

brainly.com/question/13130745

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What is the purpose of the Climate Friendly Farming Project?

Answers

The Climate Friendly Farming Project was designed to provide funding for long term research into the sustainability and adaptability of agricultural systems(wheat, vegetables, and dairy systems) as increasing greenhouse gases propagate and decline the efficiency of current agricultural practice.

Answer:

The purpose of the Climate Friendly Farming Project is to create a database of climate friendly agricultural practices

Explanation:

Edge

In electrical work, resistance is often represented by thea. Greek symbol O.
c. letter V.
b. letter I.
d. letter E.

Answers

In electrical work, resistance is often represented by the Greek symbol Ω. The correct option among all the options that are given in the question is the first option or option "a". It is actually a Greek Letter Omega and is written in upper case. I hope this is the answer you were looking for and it has helped you.

Answer : The correct option is, (a) Greek symbol O

Explanation :

Resistance : It is defined as the property of a material which resist the flow of charges through it.

Resistance is represented as, Ohm, $\Omega$ (in symbol) and uppercase Omega (in Greek symbol).

Hence, in electrical work, resistance is often represented by the Greek symbol O.

An optical telescope is an instrument that collects and _____.A. focuses light from very small objects

B. focuses light from distant objects

C. reflects light from distant objects

D. stores heat from distant objects

Answers

Answer: The correct answer is option (B)

Explanation:

Telescope is an optical device which is designed to make distant object appear nearer. It contains combination of lenses and mirrors which collects the light rays and focus them as the as magnified image.

An optical telescope is a telescope which is used to gather and focus light from visible region of the electromagnetic spectrum to form a magnified image or a photograph of distant objects .This image can be seen by the observer.

Hence ,the correct answer is option(B).

An optical telescope is an instrument that collects
and focuses light from distant objects

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