A 20 kg bike accelerates at 10 m/s2. what was the net force

Answers

Answer 1

Explanation:

Fnet = m.a

= (20)(10)

= 200N


Related Questions

what particle moves from one object to another so that the object is either positively charged or negatively charged

Answers

Answer:

electrons move causing the object to be positive or negative charged

why is m² called derived unit?​

Answers

Explanation:

The unit of energy is a derived unit because it is expressed with the help of fundamental units (kg) unit of mass and four basic units meter (m), meter (m) unit of length second (s), second (s) unit of time.


Where on the periodic table are nonmetal elements mostlikely found?
A. Along the stairstep line
B. On the right side
C. On the left side
D. At the bottom

Answers

Answer: B. On the right side

Explanation: Metals are located on the left of the periodic table, and nonmetals are located on the upper right.

The answer is.. B. The Right side.
Hope this helps!!

The farther away you are from a light source, the _____ intense it appears

Answers

Answer:

The answer is Less.

Explanation:

The further you are away from a light source, the less intense the light appears.

What is the angle of refraction for a beam of light moving from air (n =1.00) into a prism if the angle
of incidence is 70° and the prism's index of refraction is 1.73?

Answers

big sorry for this

imma follow you

Which of the following is a characteristic of a balanced force?

1) equal in size opposite in direction
2) causes a change in the direction of an object
3) causes a change in the motion of an object

Answers

1 because for example if you have two equally strong people pushing against each other they would not move
They are both equal is size or the amount of force but one is pushing to the right and one is to the left so opposite direction

Where would sound NOT be
able to travel?

A. through the ground
B. through the ocean
C. through the air
D. through outer space

Answers

The answer is D, or Outer Space.

Explanation:

Sound is implemented through mechanical wave transferral, which requires a medium (solid, liquid, or gas) to travel through. Because sound is a mechanical wave, it cannot travel through vacuums (space).

A student repeats a reaction several times to test the effects of various
changes on the reaction rate. The data table shows the results. How does
increasing the temperature of the system change thereaction rate?

A. Increasing the temperature decreases the reaction rate.
B. Increasing the temperature increases the reaction rate.
C. More information is needed to determine what happens to the reaction rate.
D. Increasing the temperature has no effect on the reaction rate.

Answers

Answer:

B. Increasing the temperature increases the reaction rate.

Explanation:

This is as with a higher temperature the particles have more kinetic energy, this is the consequece of the increase in reaction rate as the frequency of particles colliding is increased.

Answer: B

Explanation:

What is the purpose of an acid-base titration?

Answers

Answer:

the detection of the equivalence point, the point at which chemically equivalent amounts of the reactants have been mixed.

A reversible reaction is in
_______ when forward and reverse
directions of the reaction occur at the same rate so there is no overall change in the
amounts of reactants and products.

Answers

Answer:

Equilibrium

Explanation:

Equilibrium is a special situation or stage of a reactionAt equilibrium the concentrations of reactants and products are equalThe rate of change of forward and backward reaction is also same

Which of the following can refer to the form of exercise that uses free weights, weight machines, resistance bands, or the weight of the body to put stress on the muscles? A. Strength training B. Weight training C. Resistance training D. All of the above

Answers

Answer:

option C...

resistance training is the correct answer

A triangular prism made of crown glass (n=1.52) with base angles of 30.0 is surrounded by air. If parallel rays are incident normally on its base as shown in fig., what is the angle of ϕ between the two emerging rays?

Answers

Answer:

es lo que es

Explanation:

es lo que es es que slep vaka vee

the angle ϕ= will be equal to angle of refraction and it is equal to 49.4°C.

What is refractive index ?

When a light is going from medium 1 to medium 2. The refractive index is defined as a ratio of velocity of light in medium 1 to velocity of light in medium 2. Refractive index is the factor which deals with the amount of bending of light. More refractive index means more it will bend in the medium 2. When it is 1 we can say that light has not been bent.

By Snell's law, Refractive index is given by,

sin (i) ÷ sin (r) = μ₂÷μ₁

where i is the the angle of incidence

r is the angle of refraction

μ₂ & μ₁ are refractive index of medium 2 and 1 resp.

Hence it is due to Refractive index.

In this problem the light is going from prism to air, the refractive index of air is 1. From figure it is clear that the angle of incidence is 30°C.

From snell's law,

sin (30) ÷ sin (r) = μ₂÷1.52

0.5 ÷ sin (r) = 1÷1.52

0.5×1.52 = 1×sin (r)

0.76 = sin (r)

The angle of refraction r = sin⁻¹(0.76) =49.4°C

Hence angle ∅ = 49.4°C.

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7. It has been suggested that rotating cylinders about 20 km in length and 8 km in diameter be placed in space and used as colonies. The purpose of the rotation is to simulate gravity for the inhabitants. Explain this concept for producing an effective imitation of gravity.

Answers

The concept of the centrifugal force is used for producing an effective imitation of gravity. It is an important concept in the mechanics.

What is centrifugal force?

when any body is executing circular motion about a fixed axis, an outward force act on that object to balance the body and to execute the circular motion. The outward force is known as the centrifugal force.

It is the pseudo force act in order to balance the centripetal force acting inward during the circular motion.

The centrifugal force is comes into the picture when any body executes circular motion about a fixed axis.

To simulate gravity for the inhabitants, the concept of the centrifugal force is used.

Hence, the concept of the centrifugal force is used for producing an effective imitation of gravity.

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What factors affect the strength and direction of electrical forces?

Answers

Answer:

The strength of the electric field is determined by the amount of charge on the source charge (Q) and the separation distance (d) from the source charge.

Explanation:

The interaction of charged objects is a non-contact force that operates over a certain separation distance. Distance, distance, distance. Every electrical contact is accompanied by a force, emphasizing the significance of these three factors. Whether it's a plastic golf tube attracting paper bits, two like-charged balloons repelling, or a charged Styrofoam plate interacting with electrons in a piece of metal, the three crucial factors that impact the strength of the interaction are always two charges and a distance between them.  The electrical force, like all other forces, is usually measured in Newtons. The electrical interaction's intensity is a vector quantity with both magnitude and direction since it is a force. The electrical force's direction is determined by whether the charged objects are charged with similar or opposing charges, as well as their spatial orientation. With a little logic and knowledge of the two objects' charge types, the direction of the force on either of them may be determined. Objects A and B in the figure below have similar charges, hence they repel each other.

A 6.20-kg steel ball at 27.7°C is dropped from a height of 21.7 m into an insulated container with 4.50 L of water at 10.1°C. If no water splashes, what is the final temperature of the water and steel? The specific heat of steel and water is 450J / (kg - K) and 4186J / (kg - K) respectively.

Answers

The final temperature of the water and steel mixture after the steel is dropped is determined as 7.12 ⁰C.

Conservation of energy

From the principle of conservation of energy, the energy lost by the steel ball is equal to the energy gained by the water.

P.E(steel) - Thermal(steel) = Thermal(water)

mgh - mcΔθ = mcΔθ

where;

mass of water = density x volume = 1 kg/L x 4.5 L = 4.5 kg

(6.2)(9.8)(21.7) - (6.2)(450)(27.7 - T) = (4.5)(4186)(T - 10.1)

1,318.492 - 77,283 + 2790T = 18,837T - 190,253.7

114,289.192 = 16,047T

T = 7.12 ⁰C

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A few friends went skating on the frozen lake in their hometown. At one point you can hear the ice cracking. What advice can you give them so that the ice does not break and the skaters on the lake are not endangered?

Answers

Answer: i'll tell them to be careful. However, the most common is using a drill bit. Take a step close to the shore and listen for cracking. If there is cracking, do not risk going out on the ice. If there is no cracking, take a cordless drill and check the thickness using an extended drill bit.

1. The sketch shows two 4 kg blocks on a horizontal surface, joined by a string S. They are attached to a 2 kg mass by another string which passes over a frictionless pulley, allowing the 2 kg mass to hang freely. Each of the blocks experiences 6 N of friction.
a) Show that the system accelerates to the right at 0.8 m/s². Calculate the tension in string S.
b) 4 kg S 4 kg 2 kg [4] [4]

Answers

Answer:

M g - T =  M a     acceleration of hanging block   (M = 2)

2 g - T = 2 a        where M = 2

T = 2 g - 2 a

T = 8 * a + 12 N       acceleration of blocks on table

2 g - 2 a = 8 a + 12

10 a = 2 g - 12  

a = .8 m/s^2   (assuming g = 10 m/s^2)

T = 2 g - 2 a = 2 * 10 - 2 * .8 = 20 - 1.6 = 18.4 N

Check: For blocks on table

a = (18.4 - 12) / 8 = 6.4 / 8 = .8 m/s^2

A 3 kg toy plane is attached to a 1.8 m string that it can be whirled around in a horizontal circle above the users head. If one’s exerts a force of 10 N on the string, what speed should the plane have as it rotates

Answers

With the use of formula, The plane should rotate at the speed of 3 m/s

Circular Motion

When a body is moving rotationally at a point, the motion is said to be a circular motion. There are two types of motion in a circle

Vertical circular motionHorizontal circular motion

Given that a 3 kg toy plane is attached to a 1.8 m string that it can be whirled around in a horizontal circle above the users head rotates.

The given parameters are:

mass m = 3 kg

Length L = 1.8 m = radius

Force F = 10 N

Velocity V = ?

If one’s exerts a force of 10 N on the string, The speed the plane should have can be calculated by using the below formula

F = M[tex]V^{2}[/tex] / r

Substitute all the parameters into the formula

10 = 3 x [tex]V^{2}[/tex]  / 1.8

Cross multiply

18 = 3[tex]V^{2}[/tex]

[tex]V^{2}[/tex] = 18/3

[tex]V^{2}[/tex] = 9

V = [tex]\sqrt{9}[/tex]

V = 3 m/s

Therefore, The plane should rotate at the speed of 3 m/s

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3. What is the distance between New York and London, if an airplane flying at 580 Km per hour takes 7 hours to complete the trip?

Answers

Answer:

4060 km

Explanation:

580 km/hr   *  7 hr   = 4060 km

rate * time = distance

PLEASE ANSWER ASAP FOR 75 POINTS!!!!

Answers

λ = c : f

λ = 3 x 10⁸ : 1.05 x 10⁸

λ = 2.86 m

E = hf

h = Planck's constant (6.626.10⁻³⁴ Js)

E = 6.626.10⁻³⁴ x 2.86

E = 1.896 x 10⁻³³ J

λ = 3 x 10⁸ : 1.011 x 10⁸

λ = 2.97 m

E = hf

h = Planck's constant (6.626.10⁻³⁴ Js)

E = 6.626.10⁻³⁴ x 2.97

E = 1.97 x 10⁻³³ J

λ = 3 x 10⁸ : 1.05 x 10⁸

λ = 2.96 m

E = hf

h = Planck's constant (6.626.10⁻³⁴ Js)

E = 6.626.10⁻³⁴ x 2.96

E = 1.96 x 10⁻³³ J

A simple pendulum has length of 820mm. Calculate the frequency (g = 9.8 ms -2)

Answers

Answer:

[tex]\huge\boxed{\sf f=0.55 \ Hz}[/tex]

Explanation:

Given Data:

Length = l = 820 mm = 0.82 m

Acceleration due to gravity = g = 9.8 ms⁻²

Required:

Frequency = f = ?

Formula:

[tex]\displaystyle f =\frac{1}{2 \pi} \sqrt{\frac{g}{l} }[/tex]

Solution:

[tex]\displaystyle f =\frac{1}{2 \pi} \sqrt{\frac{g}{l} } \\\\Put\ the\ givens\\\\f=\frac{1}{2 \pi} \sqrt{\frac{9.8}{0.82} }\\\\ f = 0.159 \times \sqrt{11.95} \\\\f=0.159 \times 3.457\\\\f=0.55 \ Hz\\\\\rule[225]{225}{2}[/tex]

A 95kg fullback was running downfield at 8m/s. A defensive player (110kg) was running upfield at 6m/s straight at the fullback. What was the momentum of each player before they impacted?




A)Fullback: 760kgm/s, Defender: 660kgm/s

B)Fullback: 760kgm/s, Defender: -660kgm/s

C)Fullback: 570kgm/s, Defender: 880kgm/s

D) Fullback: 570kgm/s, Defender: -880kgm/s

Answers

The answer is 760kgm/a,defender

A 95 kg fullback was running downfield at 8 m/s. A defensive player (110 kg) was running upfield at 6 m/s straight at the fullback. The momentum of each player before they impacted Fullback 760 kgm/s, Defender: 660 kgm/s.

What is impulse?

In classical mechanics, the integral of a force, F, over the time period over which it acts, t, is referred to as the "impulse." Impulse is a vector quantity because force is one as well. When an item receives an impulse, it experiences an equivalent vector change in its linear momentum and also in the direction that results.

momentum = mass *velocity

momentum = 95*8 = 760 kg-m/sec Fullback

momentum = 110*6 = 660 kg-m/sec Defender

A 95 kg fullback was running downfield at 8 m/s. A defensive player (110 kg) was running upfield at 6 m/s straight at the fullback. The momentum of each player before they impacted Fullback 760 kgm/s, Defender: 660 kgm/s.

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Describe the population density located along the tectonic plate boundary known as the Ring of Fire and the potential effect that earthquakes or volcanic
activity can have in this area.

Answers

Answer:

Seventy-five percent of Earth's volcanoes—more than 450 volcanoes—are located along the Ring of Fire. Ninety percent of Earth's earthquakes occur along its path, including the planet's most violent and dramatic seismic events.

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In the early 1960s , Cuban anti-communist rebels with the assistance of the United States . Sought to regain control on Cuba from Fidel Castro . This failed military action was called what?


I NEED HELP WILL MARK YOU BRAINLIEST

Answers

Bay of pigs I believe.

Answer:

Here is the answer

Here is the answerExplanation:

Here is the answerExplanation:Bay of Pigs Invasion is the answer

Mr. McSparin can walk one mile in 0.25 hours. Calculate his velocity.

Answers

Answer:

4 mph

Explanation:

velocity =   miles divided by time =  miles/time

             =   1 mile / .25 hr   = 4 mph

An 845–g bar of ice is initially at –25 °C. The latent heat of fusion of ice is 334 kJ/kg, the specific heat of ice is 2050 J/(kg·°C), and the specific heat of water is 4180 J/(kg·°C). Determine how much energy is required if the final temperature of the system is to reach 39 °C.

Answers

Taking into account the definition of calorimetry, sensible heat and latent heat, the amount of heat required is 463.28 kJ.

Calorimetry, sensible heat and latent heat

Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.

Sensible heat is defined as the amount of heat that a body absorbs or releases without any changes in its physical state (phase change).

Latent heat is defined as the energy required by a quantity of substance to change state.

When this change consists of changing from a solid to a liquid phase, it is called heat of fusion and when the change occurs from a liquid to a gaseous state, it is called heat of vaporization.

Energy required in this case-25°C to 0 °C

In firts place, the melting point of water (temperature at which it changes state from solid to liquid) is 0°C.

So, first of all you must increase the temperature from -25 ° C (in solid state) to 0 ° C, in order to supply heat without changing state (sensible heat).

The amount of heat a body receives or transmits is determined by:

Q = c× m× ΔT

where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.

In this case, you know:

c(ice)= 2050 [tex]\frac{J}{kgC}[/tex] m= 845 g= 0.845 kgΔT= Tfinal - Tinitial= 0 °C - (-25) °C= 25 °C

Replacing:

Q1= 2050 [tex]\frac{J}{kgC}[/tex]  × 0.845 kg× 25 °C

Solving:

Q1= 43,306.25 = 43.3 kJ

Change of state

The heat Q that is necessary to provide for a mass m of a certain substance to change phase is equal to

Q = m×L

where L is called the latent heat of the substance and depends on the type of phase change.

In this case, you know:

n= 0.845 kgΔHfus= 334 [tex]\frac{kJ}{kg}[/tex]

Replacing:

Q2= 0.845 kg× 334[tex]\frac{kJ}{kg}[/tex]

Solving:

Q2= 282.23  KJ

0 °C to 39 °C

Similar to sensible heat previously calculated, you know:

c(liquid)= 4180[tex]\frac{J}{kgC}[/tex]m= 0.845 kgΔT= Tfinal - Tinitial= 39 °C - 0 °C= 39 °C

Replacing:

Q3= 4180 [tex]\frac{J}{kgC}[/tex] × 0.845 kg× 39 °C

Solving:

Q3= 137,751.9 J= 137.75 kJ

Total heat required

The total heat required is calculated as:  

Total heat required= 43.3 kJ + 282.23 kJ + 137.75 kJ

Total heat required= 463.28 kJ

In summary, the amount of heat required is 463.28 kJ.

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The amount of energy required if the final temperature of the system is to reach 39 °C is 463288.15 J

How to determine the heat required change the temperature from –25 °C to 0 °C Mass  (M) = 845 g = 845 / 1000 = 0.845 KgInitial temperature (T₁) = –25 °C Final temperature (T₂) = 0 °Change in temperature (ΔT) = 0 – (–25) = 25 °C Specific heat capacity (C) = 2050 J/(kg·°C) Heat (Q₁) =?

Q = MCΔT

Q₁ = 0.845 × 2050 × 25

Q₁ = 43306.25 J

How to determine the heat required to melt the ice at 0 °Mass (m) = 0.845 KgLatent heat of fusion (L) = 334 KJ/Kg = 334 × 1000 = 334000 J/KgHeat (Q₂) =?

Q = mL

Q₂ = 0.845 × 334000

Q₂ = 282230 J

How to determine the heat required to change the temperature from 0 °C to 39 °C Mass  (M) = 0.845 KgInitial temperature (T₁) = 0 °C Final temperature (T₂) = 39 °Change in temperature (ΔT) = 39 – 0 = 39 °C Specific heat capacity (C) = 4180 J/(kg·°C)Heat (Q₃) =?

Q = MCΔT

Q₃ = 0.845 × 4180 × 39

Q₃ = 137751.9 J

How to determine the heat required to change the temperature from –25 °C to 39 °CHeat for –25 °C to 0°C (Q₁) = 43306.25 JHeat for melting (Q₂) = 282230 JHeat for 0 °C to 39 °C (Q₃) = 137751.9 JHeat for –25 °C to 39 °C (Qₜ) =?

Qₜ = Q₁ + Q₂ + Q₃

Qₜ = 43306.25 + 282230 + 137751.9

Qₜ = 463288.15 J

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A stationary sound waves has a series of nodes. The distance between the first and the 6th node is 30cm. What is the wavelength of the sound wave

Answers

Answer:

Assume a node at the left end and the right end

N-A-N-A-N-A-N-A-N-A-N    shows nodes and anti-nodes

10 quarter wavelengths are shown  (or 2.5 wavelengths)

30 / 2.5 = 12 cm wavelength      since there is 1/4 wavelength between node and anti-node

Nodes and anti-nodes are displayed in N-A-N-A-N-A-N-A-N.

The difference between the node and the anti-node exists 12 cm wavelength.

What is meant by stationary sound waves?

Standing waves are created when two identical waves move in opposition to one another along a line. Despite being composed of two waves that are moving in opposition to one another, standing waves do not travel through space or along a string.

A wave that is stationary is one that is not moving, is at a standstill, or is in a relaxed position. A standing wave is created whenever two waves with nearly identical frequencies, wavelengths, and amplitudes that are traveling in opposite directions collide.

A waveform signal that is carried in space or down a wire has a wavelength, This is the distance between two identical locations (contiguous crests) in the following cycles. This length is typically defined in wireless systems in meters (m), centimeters (cm), or millimeters (mm).

The distance over which a periodic wave's shape repeats is known as the wavelength in physics.

Assume that there exists a node at both the left and right ends.

Nodes and anti-nodes are displayed in N-A-N-A-N-A-N-A-N.

it displays 10 quarter wavelengths.

Since there exists a 1/4 wavelength difference between the node and the anti-node, 30 / 2.5 = 12 cm wavelength.

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What do you like MOST about your chosen learning modality

Answers

The most common unimodal preference was kinaesthetic, followed by visual, auditory and read and write.

10. As a pharmacy technician, you will receive prescription orders with many different abbreviations, which will require conversions to calculate the dose. Now that you have learned about conversions and abbreviations, what would you do to fill a prescription with abbreviations? Also, what would you do with conversions you were not sure how to convert to the required dose. Explain

Answers

When you receive prescriptions that contain some abbreviations, you have to translate it into plain language that the patient can understand.

Who is a pharmacy technician?

A pharmacy technician is a skilled personnel who assists a pharmacist in a health facility. The pharmacy technician usually writes out prescriptions for patients.

When you receive prescriptions that contain some abbreviations, you have to translate it into plain language that the patient can understand. If you are not clear about the abbreviation you can ask the pharmacist for help or the doctor.

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If a constant force of 917 N is exerted on a scooter for 6 s, thenwhat is the change in momentum?

a 6 kg-m/s
b 5502 kg-m/s
c 917 kg-m/s
d 153 kg-m/s

Answers

Answer: 917

Explanation:

The change in momentum if a constant force of 917 N is exerted on a scooter for 6s is 5502kg-m/s.

How to calculate momentum?

Momentum is the tendency of a body to maintain its inertial motion. It is the product of its mass and velocity, or the vector sum of the products of its masses and velocities.

Force = mass x (velocity/time)

Force = (mass x velocity)/time

Force = momentum/time

According to this question, a constant force of 917 N is exerted on a scooter for 6s. The change in momentum is calculated as follows:

917N = p/6

p = 5502kg-m/s

Therefore, 5502kg-m/s is the change in momentum of the scooter.

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