Which situation will change the direction of the bicycle?
A. An added force of 20 N down the hill
B. Added forces of 30 N up the hill and 30 N down the hill
C. An added force of 20 N to the side of the hill
D. Added forces of 10 N up the hill and 30 N down the hill

Answers

Answer 1

Answer:

Dont know if this is right but i say C

Explanation:

Answer 2

Answer:

C. an added force of 20 N toward one side of the hill

Explanation:

I just took the quiz and got it correct./


Related Questions

difference between centrifugal and semi-centrifugal clutches​

Answers

Centrifugal clutch: These are automatic clutches under the action of centrifugal forces. ... Semi – centrifugal clutch: The manual type of clutches which have a pedal assist to it and the clutches becomes free as the system gains rpm time to time. These clutches are used to remove driver effort in racing cars.

Answer:

Semi-centrifugal clutches are used in high powered race cars, to reduce the driver effort. Working is just like semi-centrifugal clutch.

The clutch action is purely under centrifugal force.

At low engine rpm the centrifugal force is low, so there is slip, as engine rpm increases, so does the centrifugal force.

Aluminum has a shear strength of 210 megapascals. When you bend aluminum foil around an edge (i.e., the edge of the box) and pull, you are effectively applying a shear force along the bent edge of the foil. If a roll of household aluminum foil is 30.0 centimeters wide and its thickness is approximately 15.0 micrometers, how much shear force is needed to pull off a sheet

Answers

Answer:

The answer is "[tex]945\ N[/tex]"

Explanation:

Aluminum has 210 megapascals of tensile resistance. They choose a shear force only at bent foil edge to bend aluminum foil over an edge (that is the edge of its box) to pull them. When a roll of aluminium domestic foil is 30 cm in width and about 15.0 micrometers.

[tex]\to 0.000015 \times 0.300 = 0.0000045\\\\\to 210000000 = \frac{F}{0.0000045}\\\\\to F=210000000 \times 0.0000045\\\\\to F = 945\ N[/tex]

A chain is wrapped around pulley and pulled with a force of
16.0N .The pulley has a radius of 0.20 m. The pulley's rotational
speed increases from 0.0 to 17.0 rev/min in 5.00s What is the moment
of inertia of Pulley?

Answers

The moment of inertia of Pulley is 8.89 kgm².

Angular acceleration of the pulley

The angular acceleration of the pulley is calculated as follows;

[tex]\alpha = \frac{\omega_f - \omega _i}{t}[/tex]

where;

ωi is the initial angular velocity = 0 ωf is the final angular velocity = 17 rev/mint is the time of motion

Final angular velocity in radian per second is calculated as

[tex]\omega _f = 17 \frac{rev}{\min} \times \frac{2\pi \ rad}{1 \ rev} \times \frac{1\min}{60 \ s} = 1.78 \ rad/s[/tex]

Now, solve for angular acceleration

[tex]\alpha = \frac{1.78-0}{5} \\\\\alpha = 0.36 \ rad/s^2[/tex]

Moment of inertia of the pulley

The the moment of inertia of Pulley is determined using the formula for torque.

Iα = Fr

I = Fr/α

I = (16 x 0.2)/(0.36)

I = 8.89 kgm²

Thus, the moment of inertia of Pulley is 8.89 kgm².

Learn more about moment of inertia here: https://brainly.com/question/25803184

9
A canoe with a mass of 120 kg is floating downriver at a speed of 2.5 m/s. What is the canoe's kinetic eergy?

Answers

Answer:

K.E. = ½ × mv²

= ½ × 120 × (2.5)²

= 60 × 6.25

= 375 J

Which of the following is an example of a noncontrolled substance?
A. Sleeping pills
B. Coffee
C. Pain medications
D. Cough medications
SUBMIT

Answers

An example of noncontrolled substance from the option is Cough medications.

What are Noncontrolled substances?

Noncontrolled substances are substances that are prescribed by medical personnel or pharmaceutical professionals for treatment of a disorder or ailments that is affecting a person.

Noncontrolled substances include medications that are majorly prescribed for treatment of medical conditions like high blood pressure, diabetes, and bacterial infections.

Therefore, An example of noncontrolled substance from the option is Cough medications.

Learn more about noncontrolled substances below.

https://brainly.com/question/5349491

Which theory states that the principle cause of forgetting is passage of time? A. motivated forgetting B. retrieval failure C. decay theory D. ineffective encoding

Answers

Decay theory

As time passes the information is less available for later retrieval, so that the information won’t be lost over time it is necessary to rehearse it.

Mu
wann-A
Very Short Answer Type Questions
1. Name the nutrients present in our food which give mainly energy to our body.
2. Name the nutrient which is needed for the growth and repair of our body. Proteins
3. Name the main carbohydrate which we eat in our food. I heat Rica maizes Pearl Potato
4. Which carbohydrate is present in wheat, rice and potatoes ? Plants
5. Name two foods each rich in (a) fats, and (b) starch. Batterheen
6. Name the major nutrients in our food.Combshed soles Fats Rooten mineral water Vitamin
7. Name the vitamin which is required for maintaining good eyesight Witamin A
8. Name the vitamin which keeps the teeth, gums and joints healthy, and helps fight diseases. 14
9. Name the vitamin which is necessary for the normal growth of bones and teeth Wermico
10. Which vitamin is produced in the human body when skin is exposed to sunlight ? uamu-D
11. Name the main vitamin present in (a) oranges, and (b) carrots. Worthing
12 Name an important mineral present in (a) apple, and (b) sea-fish.
13. Which mineral is needed to make haemoglobin present in our red blood cells.
14. In addition to calcium, which other mineral is needed for making bones and teeth ? (chum, Pha
15. Name a mineral which is needed for keeping bones and teeth healthy.
16. Which mineral is needed for the proper functioning of thyroid gland ?
17. Name two food materials which contain a lot of water. Fresh forest
18. Name the component of our food which helps prevent constipation. bulk oftend, wollte man
Vegetable
19. What is the other name of roughage? Dletary Abu
29Which component of food is mainly made of indigestible carbohydrate 'cellulose'?
21. The examples of carbohydrates are : sugar, cellulose, glucose and starch. Which of these carbohydrate
provides roughage in our food ?
22. Name two components of food which do not provide any nutrients.Cellulog
23. Fill in the following blank with a suitable word :
Iron is an important constituent of.........present in our blood. Hemoglobin
Short Answer Type Questions
24. What is the function of fats in our body? Name​

Answers

1. carbohydrates, proteins, fats, vitamins and minerals.

2. blood and muscle cells

3. fructose, glucose, and lactose)

4. Fiber and protein

5. Avocados and potato

6. carbohydrates, proteins, fats, vitamins and minerals.

7.vitamin A
8. Vitamin C
9.vitamin D
10. Vitamin D
11.vitamin C
12. calcium, potasium and phosphorus.
13. myoglobin and iron
14.Vitamin D
15.calcium
16.Lodine
17. Cucumber tomato
18. Fiber
19.dietary fibers
20.starch and sugars
21. I don’t know
22.roughaghe and water

a student throws a coin vertically downward frok the top of a building. the coin leaves the throwers hand with a speed of 15.0m/s. what is its speed after falling freely for 2.00s?​

Answers

Answer:

Final speed after 2 seconds = 34.6 m/s

Explanation:

Given:

Initial speed of coin (u) = 15 m/s

Time taken = 2 seconds

Find:

Final speed after 2 seconds

Computation:

Gravitational acceleration of earth = 9.8 m/s²

Using first equation of motion;

v = u + at

or

v = u + gt

where,

v = final velocity

u = initial velocity

g = Gravitational acceleration

t = time taken

v = 15 + 9.8(2)

v = 15 + 19.6

Final speed after 2 seconds = 34.6 m/s


Write a paragraph descibing three rides in an amusement park and how rides cause you
to move.

Answers

Answer:

Hope this helps!  can I have brainliest im trying to level up.

Explanation:

Bumper cars are a great place to see Sir Isaac Newton’s three laws of motion in action. Here’s how:

Newton’s First Law: Every object in motion continues in motion and every object at rest continues to be at rest unless an outside force acts upon it.

This is because all objects have inertia – the property of matter that resists changes to the object’s motion.

Newton found that if a ball is sitting on a table, it will stay sitting there because that is what it ‘wants’ to do.

If the ball is set in motion, it will keep traveling in a straight path because, again, that is what it ‘wants’ to do.

An object in motion will not stop, slow down, or change its direction unless an outside force acts on it (such as gravity, friction, and air resistance).

When you are riding in a bumper car and end up in a collision with another bumper car, you feel a jolt. This is because your body’s inertia wants it to keep traveling in the direction it was moving with the car even though your bumper car has now suddenly stopped.

Newton’s Second Law: The greater the mass of an object, the harder it is to change its speed.

(More force is needed to move it.)

You already know this law and practice it in your everyday life. Something that is small, such as a pebble, is much easier to pick up and throw than something that is large and heavy, such as a boulder.

When riding in the bumper cars, you may have noticed that people who weigh less tend to get pushed around more than people who weigh more.

The more mass (weight) an object has, the more force it takes to move it.

And since all the bumper cars usually have the same top velocity, the cars carrying more mass will never travel as far as the cars carrying less mass after a collision.

Newton’s Third Law: For every action, there is an equal and opposite reaction.

If two bumper cars traveling at the same speed and carrying the same amount of weight run into each other, they will bounce off and move an equal distance away from each other.

And based on the second law, if there is a difference in the amount of weight being carried in the two cars, the car with less weight will travel farther away from the point of impact than the car carrying more weight.

How much current is drawn by a television
with a resistance of 43 Ω that is connected
across a potential difference of 112 V?
Answer in units of A.

Answers

Answer:

Explanation:

v = ir

v/r = i

112/43 = i

2.60 ≈ i

How are rainbows made?

Answers

When it rains thin the sun comes out thin a rainbow appears

Answer:

when it rains and at the same time it sunny there would appear a rainbow

What is the wavelength associated with 0.113kg ball traveling with velocity of 43 m/s?

Answers

Answer:

Wavelength = 1.36 * 10^{-34} meters

Explanation:

Given the following data;

Mass = 0.113 kg

Velocity = 43 m/s

To find the wavelength, we would use the De Broglie's wave equation.

Mathematically, it is given by the formula;

[tex] Wavelength = \frac {h}{mv} [/tex]

Where;

h represents Planck’s constant.

m represents the mass of the particle.

v represents the velocity of the particle.

We know that Planck’s constant = 6.6262 * 10^{-34} Js

Substituting into the formula, we have;

[tex] Wavelength = \frac {6.6262 * 10^{-34}}{0.113*43} [/tex]

[tex] Wavelength = \frac {6.6262 * 10^{-34}}{4.859} [/tex]

Wavelength = 1.36 * 10^{-34} meters

space question 50 points
Explain how sun angle and seasons vary as you move away from the equator.

Answers

Seasonal change in the angle of sunlight, caused by the tilt of the Earth's axis, is the basic mechanism that results both in warmth of the weather and in length of the day.

how much work is done in accelerating a 2000 kg car from rest to a speed of 30 m/s?

Answers

The work done is the same as the amount of energy increase. The formula for kinetic energy is 122
1
2
m
v
2
.

The initial KE of the car is 12(1000)×202=200,000
1
2
(
1000
)
×
20
2
=
200
,
000
joules.

The final KE of the car is 12(1000)×302=450,000
1
2
(
1000
)
×
30
2
=
450
,
000
joules.

The difference between these is the amount of work done: 450,000−200,000=250,000
450
,
000

200
,
000
=
250
,
000
joules.
14.2K viewsView upvotes

20



3

Which object orbits object E?
A
B
C
Or D

Answers

Answer:

its D I hope this helps you

imagine a single charge creating an electric field. what is the relationship between electric field strength and the distance from the charge?
a. direct
b. inverse
c. inverse squared
d. indirect

Answers

Answer:

b. inverse

Explanation:

[tex]E = \frac{V}{d} \\ d \: is \: the \: distance \\ [/tex]

A ball is rolling away from you at a constant speed, hits a wall, and then suddenly stops moving. Imagine a position-versus-time graph showing the ball’s motion. Describe the line on the graph.

Answers

Answer:

It would show a "straight line".

Explanation:

Newton's First Law of Motion states that an object at rest will remain at rest and an object in motion will remain in motion (at a constant velocity) unless acted upon by an unbalanced force. Newton's first law of motion is also called the law of inertia.

Spiral fracture of bone: Spiral fracture of bone occurs due to twisting of the limb, and is a very common skiing accident. The fracture plane is helical, and is very difficult to heal. Mechanically, it occurs due to an applied torsion load on the bone. Recall that a state of pure shear occurs within the material when torsion is applied on a cylinder, and the bone can be idealized as a cylinder. Let a femur bone be subjected to a torque of T 50 N-m. Assume body weight of the person to be W- 80 Kgs, while each leg is subjected to half of that weight. Given radius of the bone r 10 mm. Compute the principal stresses and shear stresses, as well as orientation of planes on which these stresses are realized.

Answers

Answer:

principal stresses :б1 = 32.62mPa  б2 = 31.38mPa

Max Shear stress : 16.31 mPa

Orientation of max principle plane = 44.43°

Orientation of minimum principal plane = 134.43°

Explanation:

Given data:

Torque = 50 N-m

weight = 80 kgs

half of weight is subjected to each leg

radius of bone = 10 mm = 0.010 m

a) Determine the principal stresses and shear stress

first calculate the max shear stress ( this will occur in the outermost element

= 16T / π*d^3   where : T = 50 , d = 0.020 m

hence max shear stress = 32 mPa

next determine compressive stress

= ( 40*g)  / π/4*d^2 . where : d = 0.020 m , g = 9.81

hence compressive stress = 1.24 mPa

draw and calculate the radius of Mohr's circle

radius of Mohr's circle = 32.0060

Hence principal stresses = 32.0060 ± 0.62

б1 = 32.62mPa  

б2 = 31.38mPa

attached below is the remaining part of the solution

Ali is sitting on the chair, identify the forces acting on him.

Answers

one force acting on him is gravity
gravity and the chair pushing up against him

19
What is the mass of a ball that is traveling 30 m/s and has 4.5 J of kinetic energy?
ave a GPF of 35512

Answers

Answer: The mass of ball is 10 grams.

Explanation:

Given : Kinetic energy = 4.5 J

Velocity = 30 m/s

The formula for Kinetic energy is as follows.

[tex]K.E = \frac{1}{2}mv^{2}[/tex]

where,

K.E = Kinetic energy

m = mass

v = velocity

Substitute the values into above formula as follows.

[tex]K.E = \frac{1}{2}mv^{2}\\4.5 J = \frac{1}{2} \times m \times (30 m/s)^{2}\\m = \frac{4.5 J \times 2}{900 m^2/s^2} (1 Js^{2} = kg m^{2})\\= 0.01 kg (1 kg = 1000 g)\\= 10 g[/tex]

Thus, we can conclude that the mass of ball is 10 grams.

There is a current of 0.83 A through a light bulb in a 120.0v circuit. What is the
resistance of the light bulb?

Answers

Answer:

144.6ohms

Explanation:

v=IR

R =V/I=120/0.83

R=144.6

Find the current passing through each of the 3 resistors connected parallel to each other as shown in the figure (i1, i2, I3). Show your actions clearly.

Answers

Answer:

I1 = ε/R1

I2 = ε/R2

I3 = ε/R3

Explanation:

From the image, we see that the resistors are connected in parallel. This means that the voltage passing through them is the same.

Now, formula for current is; I = V/R

In this case, V which is voltage is denoted by ε.

Thus;

I1 = ε/R1

I2 = ε/R2

I3 = ε/R3

Calculate the height of a cliff if it takes 2.35s for a rock to hit the ground when it is thrown straight up from the cliff with a initial velocity 8m/s.​

Answers

Answer:

y₀ = 10.625 m

Explanation:

For this exercise we will use the kinematic relations, where the upward direction is positive.

         y = y₀ + v₀ t - ½ g t²

in the exercise they indicate the initial velocity v₀ = 8 m / s.

when the rock reaches the ground its height is zero

         0 = y₀ + v₀ t - ½ g t²

        y₀i = -v₀ t + ½ g t²

let's calculate

         y₀ = - 8  2.5 + ½  9.8  2.5²

         y₀ = 10.625 m

Suppose that a particle accelerator is used to move two beams of particles in opposite directions. In a particular region, electrons move to the right at 4910 m/s and protons move to the left at 2583 m/s. The particles are evenly spaced with 0.0758 m between electrons and 0.0577 m between protons. Assuming that there are no collisions and that the interactions between the particles are negligible, what is the magnitude of the average current in this region

Answers

Answer:

The answer is "[tex]17.28 \times 10^{-14}\ A[/tex]"

Explanation:

Calculating the number of electrons passing in per second:

[tex]\to n_e = \frac{4910}{0.0758} = 6.4 \times 10^5[/tex]

Calculating the current in electron:

[tex]\to I_e = 6.4 \times 10^5 \times 1.6 \times 10^{-19} = 10.24 \times 10^{-14}\ A[/tex]

Calculating the number of protons passing in per second:

[tex]\to n_p = \frac{2583}{0.0577} = 4.4 \times 10^{4}[/tex]

Calculating the current in proton:

[tex]\to I_p = 4.4 \times 10^{4} \times 1.6 x 10^{-19} = 7.04 \times 10^{-14} \ A[/tex]

Calculating the total current:

[tex]\to I = I_p + I_e = 17.28 \times 10^{-14}\ A[/tex]

Three capacitors, C1 = 2 μF, C2 = 4 μF, C3 = 4 μF, are connected in series Determine the capacitance of a single capacitor that will have the same effect as the combination.​

Answers

Answer:

1 μF

Explanation:

To obtain the answer to the question, all we need to do is to calculate the equivalent capacitance of the capacitors. This can be obtained as illustrated below.

From the question given above, the following data were obtained:

Capacitor 1 (C₁) = 2 μF

Capacitor 2 (C₂) = 4 μF

Capacitor 3 (C₃) = 4 μF

Equivalent capacitance (Cₑq) =?

Cₑq = 1/C₁ + 1/C₂ + 1/C₃

Cₑq = 1/2 + 1/4 + 1/4

Cₑq = (2 + 1 + 1)/4

Cₑq = 4/4

Cₑq = 1 μF

Thus, the answer to the question is 1 μF

The light waves transfer their oscillations and energy to other object in what way?

The frequency of the light waves physically causes the object to move
The energy of the light wave transfers to the electrons of the material which causes them to gain that energy
The wavelength of the light changes the velocity of the atoms in the material
The amplitude of the light will affect how much of it shines on the object

Answers

Answer: b the energy of light...

Explanation:

An old shade-tree mechanic trick for removing a stubborn bolt is to slip a long pipe over the handle of the wrench, then apply a force to the end of the pipe opposite the bolt.

Why is this effective? What problems might this technique cause?

Answers

Answer: long pipe is used to increase torque and reduce force needed.

Explanation: A torque is needed to open bolt. torque = F·r, if

R increases, Force F needed to open bold is smaller.

Problem is a worn bolt may break down. It sometimes I send useful to heat bolt instead using too much power.

A string with a length of 0.75 m is fixed at both ends. (a) What is the longest possible wavelength for the traveling waves that can interfere to form a standing wave on this string? (b) If waves travel with a speed of 130 m/s on this string, what is the frequency associated with this longest wavelength?

Answers

Answer:

a) Longest wavelength is: [tex]\lambda_{1}=2*0.75=1.5\: m[/tex]

b) The frequency associated with this longest wavelength is: [tex]f=86.7\: Hz[/tex]

Explanation:

a)

The wavelength equation of a standing wave is given by:

[tex]\lambda_{n}=\frac{2}{n}L[/tex]

Where:

L is the length of the stringn is a natural number

We use n=1 to find the longest possible wavelength, so we will have:

[tex]\lambda_{1}=2L[/tex]

[tex]\lambda_{1}=2*0.75=1.5\: m[/tex]

b)

The speed of the wave is given by:

[tex]v=f\lambda[/tex]

So we just need to find the f (frequency).

[tex]f=\frac{v}{\lambda}[/tex]

[tex]f=\frac{130}{1.5}[/tex]

[tex]f=86.7\: Hz[/tex]

I hope it helps you!

A beaker is filled with water. A small plastic container contains a solid bar of aluminum, which has a mass of 40 g, and is placed on the water so that it floats. The water level reads 60 ml. Next, the bar of aluminum is taken out of the container and placed in the water so that it sinks to the bottom. By how much does the water level change?

Answers

Answer:

25.2 ml

Explanation:

When the aluminium block is inserted in the container, the overall amount of only the water in the beaker can equal V o.

The weight of the water expelled by the plastic container should be equal to the weight of the aluminium block, according to the buoyancy balance relation.

i.e.

[tex]\rho_w V_wg = m_{Al}g = \rho_{Al}V_{Al} g \\ \\ V_w = \dfrac{\rho_{Al}V_{AL}}{\rho_{w}}[/tex]

When the aluminium block is inserted into the plastic container, the initial volume of water = 60 ml

[tex]V_i = V_o + V_w[/tex]

[tex]V_i = V_o + \dfrac{\rho_{Al}V_{Al}}{\rho_{w}}---(1)[/tex]

When the aluminium block is placed outside the container, the volume of the water

[tex]V_f = V_o +V_{Al} ---(2)[/tex]

By subtracting equation (1) and (2)

[tex]V_i -V_f = V_o + \dfrac{\rho_{Al} V_{Al}}{\rho_w}- ( V_o + V_{Al}}) \\ \\ =\dfrac{\rho _{Al}V_{Al}}{\rho_w}-V_{Al} \\ \\ = V_{Al} \Big( \dfrac{\rho_{Al}}{\rho_{w}}-1 \Big)[/tex]

since;

[tex]m_{Al} = 40 g[/tex]

[tex]V _{Al} = \dfrac{40 \ g}{2.7 \ g/cm^3} \\ \\ V_{Al} = 14.815 \ cm^3[/tex]

Similarly;

[tex]\dfrac{\rho_{Al}}{\rho_{w}}= \dfrac{2.7 }{1.0}[/tex]

= 2.7

[tex]V_i -V_f =14.815\Big( 2.7-1 \Big) \\ \\ V_i -V_f = 25.1855 \ ml \\ \\ = \mathbf{25.2 \ ml}[/tex]

what the answer for this question ?

Answers

Answer:

Explanation:

It is better to say “It is correct.” The word THIS is a demonstrative pronoun. The word THIS should be used to point out or to indicate the things. The word CORRECT is an abstract noun therefore it can not be pointed out this is why it is better to say IT IS CORRECT.

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