Mature salmon swim upstream, returning to spawn at their birthplace. During the arduous trip they leap vertically upward over waterfalls as high as 2.83 m. With what minimum speed (in m/s) must a salmon launch itself into the air to clear a 2.83-m waterfall

Answers

Answer 1

Answer: minimum speed of launch must be 7.45m/s

Explanation:

Given the following:

Height or distance (s) = 2.83m

The final velocity(Vf) at maximum height = 0

Upward motion, acceleration due to gravity(g) us negative = -9.8m/s^2

From the 3rd equation of motion:

V^2 = u^2 - 2gs

Where V = final velocity

u = initial velocity

Therefore, u = Vi

u = √Vf^2 - 2gs

u = √0^2 - 2(-9.8)(2.83)

u = √0 + 55.468

u = √55.468

u = 7.4476 m/s

u = 7.45m/s


Related Questions

An object of mass 800g hangs on a spring. Calculate the force exerted by the object if acceleration due to gravity is 10/s2​

Answers

Answer:

8 N

Explanation:

Using the equation F=ma (F: force/ m: mass  in kg/ a: acceleration),

F = (800/1000)(10)

F = 8 N

The photons of different light waves:

Answers

Answer:

(C)

Explanation:

Because the photons being different makes them have different amounts of energy, they both with have a precise and different energy from each other.

A convex lenses forms a real image of an object magnified two times. The distance between the object and image is 60cm. Find the focal lenth of the lense

Answers

Answer:

13.3cm ≈ 13cm

Explanation:

The following data were obtained from the question:

Magnification (M) = 2

Distance between image and object = 60cm

Focal length (f) =..?

Next, we shall determine the image distance (v) and the object distance (u). This can be obtained as follow:

Magnification (M) = image distance (v) / object distance (u)

M = v/u

Magnification (M) = 2

2 = v/u

Cross multiply

v = 2u

From the question,

Distance between image and object = 60cm i.e

v + u = 60

v = 2u

2u + u = 60

3u = 60

Divide both side by 3

u = 60/3

u = 20cm.

v = 2u = 2 x 20 = 40cm

Now, we can obtain the focal length of the lens as follow:

1/f = 1/v + 1/u

u = 20cm.

v = 40cm

1/f = 1/v + 1/u

1/f = 1/40 + 1/20

1/f = (1 + 2)/40

1/f = 3/40

f = 40/3

f = 13.3cm ≈ 13cm

Therefore, the focal lenth of the lens is 13.3cm ≈ 13cm

A toy car accelerates from 3m/s to 5m/s in 5sec . what is the acceleration​

Answers

Answer:

0.4

Explanation:

Because 3m/s is the initial velocity(u) and 5m/s is the final velocity(v) and time is 5 sec.

So, acceleration = v-u ÷ t

I'm confused

A 13,500 kg railroad freight car travels on a level track at a speed of 4.5 m/s. It collides and couples with a 25,000 kg second car, initially at rest and with brakes released. What is the speed of the two cars after collision?

Answers

Answer:

V = 1.578m/s

Explanation:

(Ma x Ua) + (Mb x Ub) = (Ma + Mb)V

(13500 x 4.5) + (25000 x 0) = (13500 + 25000)V

60750 + 0 = (38500)V

60750 = 38500V

V = 60750/38500

V = 1.578m/s

The speed of the two cars after the collision will be equal to V = 1.578m/s

What is collision?

A collision is any event in which two or more bodies exert forces on each other in a relatively short time. Although the most common use of the word collision refers to incidents in which two or more objects collide with great force, the scientific use of the term implies nothing about the magnitude of the force

Now from the perfectly inelastic collision, the conservation of momentum will be

(Ma x Ua) + (Mb x Ub) = (Ma + Mb)V

(13500 x 4.5) + (25000 x 0) = (13500 + 25000)V

60750 + 0 = (38500)V

60750 = 38500V

V = 60750/38500

V = 1.578m/s

Hence the speed of the two cars after the collision will be equal to V = 1.578m/s

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The index of refraction of a clear plastic is listed as 1.89 in the book, but you measured the angle of incidence 63.5° and the angle of refraction 32°. What index of refraction did you calculate and what is the percentage error?

Answers

Answer:

index of refraction = 1.69percentage error = 10.58%

Explanation:

According to Snell's law, the ratio of the sine of angle of incidence to the sine of angle of refraction is a constant for a given pair of media. The constant is known as the refractive index.

Mathematically [tex]\frac{sin i}{sin r} = n[/tex]

i = angle of incidence measured = 63.5°

r = angle of refraction measured = 32°

n = refractive index

[tex]n = \frac{sin 63.5^{0} }{sin 32^{0} } \\n = \frac{0.8949}{0.5299}\\ n = 1.69[/tex]

The index fraction calculated is approx. 1.69.

If the index of refraction of a clear plastic as listed in the book is 1.89 and the calculated is 1.69, the percentage error will be calculated as thus;

%error = [tex]\frac{1.89-1.69}{1.89} * 100[/tex]

%error = [tex]\frac{0.2}{1.89}*100[/tex]

%error  = [tex]\frac{20}{1.89}[/tex]

%error  = 10.58%

For the following elementary reaction 2br• -> br2-. The rate of consumption of the reaction and the rate of formation of product is given by which set of expression? ​

Answers

Answer: [tex]-\frac{1}{2}\times \frac{d[Br^.]}{dt}=+\frac{d[Br_2]}{dt}[/tex]

Explanation:

Rate of a reaction is defined as the rate of change of concentration per unit time.

Thus for reaction:

[tex]2Br^.\rightarrow Br_2[/tex]

The rate in terms of reactants is given as negative as the concentration of reactants is decreasing with time whereas the rate in terms of products is given as positive as the concentration of products is increasing with time.

[tex]Rate=-\frac{d[Br^.]}{2dt}[/tex]

or [tex]Rate=+\frac{d[Br_2]}{dt}[/tex]

Thus [tex]-\frac{d[Br^.]}{2dt}=+\frac{d[Br_2]}{dt}[/tex]

What us meant by Velocity ratio of simple machine is 4?


Answers

The force ratio of a machine is 4 and it velocity ratio is 4 means that the load moved is four times the effort applied and the distance moved by the effort is five times the distance moved by the load at the same time interval.



Please mark as brainliest

A velocity vs. time graph is shown. A graph titled Velocity versus Time shows time in seconds on the x axis, numbered 0 to 5, velocity in meters per second on the y axis, numbered 0 to 20. A line starts at the origin and ends at (5, 20). What is the acceleration of the object?

Answers

Answer:

[tex]a = 4 \frac{m}{s {}^{2} } [/tex]

Explanation:

u for velocity

t for time

a for acceleration

[tex]u = a \times t \\ 20 = a \times 5 \\ a = \frac{20}{5} \\ a = 4[/tex]

That's it! Hope I helped!

A Jaguar XK8 convertible has an eight-cylinder engine. At the beginning of its compression stroke, one of the cylinders contains 499cm3499cm 3 of air at atmospheric pressure (1.01×105Pa)(1.01×10 5 Pa) and a temperature of 27.0∘C27.0 ∘C. At the end of the stroke, the air has been compressed to a volume of 46.2cm 346.2cm 3 and the gauge pressure has increased to 2.72×106Pa2.72×10 6Pa. Compute the final temperature.

Answers

Answer:

503°C

Explanation:

According to the given situation, the computation of the final temperature is shown below:

In this question we use the law of ideal gas i.e

pV = nRT

i.e

[tex]\frac{p_1V_1}{T_1} = \frac{p_2V_2}{T_2}[/tex]

Therefore

[tex]T_2 = T_1 (\frac{p_2}{p_1}) (\frac{V_2}{V_1})[/tex]

[tex]= 300\ k (\frac{2.72 \times 10^{6} Pa + 1.01 \times 10^{5} Pa}{1.01 \times 10^{5} Pa})(\frac{46.2 cm^3}{499 cm^3})[/tex]

= 776 k

= (776  - 273)° C

= 503°C

Therefore the final temperature is 503°C

We simply applied the above formulas so that the final temperature could arrive

an astronaut is said to be weightless when he/she travels in a satellite.does it mean that the earth does not attract him/her?​

Answers

Answer:

No, gravitational force is a force having infinite range. It only reduces to an extent that astronauts cannot feel it.

Explanation:

a) Under what circumstances would a constant force result in increasing acceleration on a body? b) Under what circumstances would a constant force result in zero acceleration on a body?

Answers

Answer:

Remember the equation:

F = m*a

where F is force, m is mass and a is acceleration.

If we have F constant. and we want that increases, then we can have the case where m decreases.

The mass can decrease in cases like a rocket, where as the fuel of the rocket consumes, the mass of the rocket decreases and the acceleration increases.

b) The cases where a constant force results in a constant acceleration of zero, is when the force is canceled, an example of this is the constant force of the gravity in all the objects. The objects that are in the ground are being affected by this force, but the gravitational force is canceled with the normal force of the ground. Then we have a constant force that does not cause any acceleration.

In physics what does 7.56 × 5.746 equal ?

Answers

Answer:

43.43

Explanation:

5.746 x 7.56 = 43.43976

As the least number of desimal is two so our awnser should contain two digits after the decimal point.

Ans: 43.43.

Answer:

43.4 (Plato/Edmentum)

Explanation:

#1: 7.56 * 5.746

#2: 43.43976

#3: 43.4

Question 7 of 20
A technician is checking a circuit for voltage. In this instance, the voltage reads 4.2v instead of 5v
at the connector. What caused the voltage to read lower than normal?
High current flow
Low resistance
High resistance
High voltage
Next​

Answers

Answer:

High current flow

Explanation:

Generally , the measuring instruments used by technician also have some resistance, though its value is very low  . So when high current is present in the circuit , that current also passes through the instrument which creates a good potential drop across the instrument . So the external voltage used in the circuit measures less voltage .

What must be included when describing the displacement of an object?

Answers

Answer:

the unit must always be indicated

Explanation:

displacement is alway in metre (m)

Answer:

A: measurement and direction

Explanation:

on edge! hope this helps!!~ (≡^∇^≡)

A woman is standing on a steep hillside in the rain and is not moving. A
sudden gust of wind blows down the hillside, which makes her start sliding
down the hill. When the wind stops blowing, the woman continues to slide.
Which of the following statements explains why she continues to slide down
the hillside?
A. The component of the woman's weight along the hillside is larger
than the kinetic friction between the woman and the ground.
B. The component of the woman's weight along the hillside is less
than the kinetic friction between the woman and the ground.
C. The component of the woman's weight along the hillside is larger
than the static friction between the woman and the ground.
D. The component of the woman's weight along the hillside is less
than the static friction between the woman and the ground.
SUBMIT

Answers

Answer:

The correct option is;

A. The component of the woman's weight along the hillside is larger than the kinetic friction between the woman and the ground

Explanation:

Given that the coefficient of static friction is always larger than the coefficient of kinetic friction, we have that before the wind blew, the component of the woman's weight along the hillside was lesser than the static friction between  the woman and the ground, when the wind blew the total force of the wind and the component of the woman's weight put her into motion such that the acting frictional force was then the kinetic frictional force which was lesser than the kinetic frictional force so the woman continues to slide down the hillside without the wind.

What is the meaning of wwe​

Answers

Answer:

World Wrestling Entertainment, Inc., d/b/a WWE, is an American integrated media and entertainment company that is primarily known for professional wrestling. WWE has also branched out into other fields, including movies, football, and various other business ventures.

Answer:

This means WORLD WRESTLING ENTERTAINMENT.

Explanation:

This is an american integrated media and entertainment company that is primarily known for PROFESSIONAL WRESTLING.

Jasper made a list of the properties of electromagnetic waves. Identify the mistake in the list. Electromagnetic Wave Properties 1. Are made up of an electric field and a magnetic field 2. Are longitudinal waves 3. Can travel through space 4. All travel at the same speed in a vacuum Line 1 has a mistake. Line 2 has a mistake. Line 3 has a mistake. Line 4 has a mistake.

Answers

Answer:

Statement 2 is wrong

Explanation:

To check the statements in this exercise, let's describe the main properties of electromagnetic waves. Let's describe the characteristics

* they are transverse waves

* formed by the oscillations of the electric and magnetic fields

* the speed of the wave is the speed of light

with these concepts let's review the final statements

1) True. Formed by the oscillation of the two fields

2) False. They are transverse waves

3) True. Can travel by vacuum as they are supported by oscillations of the electric and magnetic fields

4) True. They all have the same speed of light

Statement 2 is wrong

100 POINTS! I will mark brainliest! Record your hypothesis as an “if, then” statement for the rate of dissolving the compounds: Record your hypothesis as an “if, then” statement for the boiling point of the compounds:

Answers

Answer:

Rate of dissolving compounds:

If we increase the temperature of the solution, then the dissolving compound would dissolve more easily.

Boiling Point of Compounds:

If the inter-molecular forces of any compound is really strong, then the boiling point of the compound would be really high.

Answer: This is just re worded from the other answer to give a different saying to the responce.

Record your hypothesis as an “if, then” statement for the rate of dissolving the compounds: If we increase the temperature then the compound will dissolve easier. 

Record your hypothesis as an “if, then” statement for the boiling point of the compounds: If the forces of the compound itself is strong, then the boiling point would be way higher.

identify units for volts

Answers

Answer:

Volts itself is SI Unit of Electric Potential.

Explanation:

Electrical Parameter. Measuring Unit

Voltage. Volt. Symbol
V or E

Find the net force and acceleration. 10 points. Will give brainliest.

Answers

Answer:

a) 16 N

b) 2.13 m/s²

Explanation:

Draw a free body diagram of the tv stand.  There are four forces:

Weight force mg pulling down,

Normal force N pushing up,

Friction force Nμ pushing left,

and applied force P pulling right.

Sum of forces in the y direction:

∑F = ma

N − mg = 0

N = mg

The net force in the x direction is:

∑F = P − Nμ

∑F = P − mgμ

∑F = 25 N − (7.5 kg) (10 m/s²) (0.12)

∑F = 16 N

Net force equals mass times acceleration:

∑F = ma

16 N = (7.5 kg) a

a = 2.13 m/s²

[tex]\mathfrak{\huge{\pink{\underline{\underline{AnSwEr:-}}}}}[/tex]

Actually Welcome to the Concept of the FRICTION.

Force by Xavier = 25 N

Force of friction in the opposite direction of Xavier = f = umg

where, u = coefficient of kinetic friction.

so we here get as ,

Net force = 16 N

and acceleration = 2.13 m/s^2

A ball is launched upward at an angle from the ground. Which way does its velocity point at the top?
A. Vertical
B. It isn't moving
C. Horizontal
D. Horizontal and Vertical

Answers

The answer is B because at the very top the acceleration is ZERO so it isn’t moving

Answer the following questions regarding the equation:

N₂ + 3H₂ → 2NH₃

1) indicates what type of reaction is
2) what represents the coefficients 3 and 2 in the previous reaction is done for
3) What would be missing in the previous equation to make it more accurate is

Answers

Explanation:

1) This is a synthesis reaction (two or more reactants combine to form a single product).

2) The coefficients are added to balance the reaction.

3) Adding the states of matter (solid, liquid, gas) will make the reaction more precise.

Assessment started: undefined. Item 1 Which statement accurately describes what happens when ice melts in terms of energy? A:The ice releases energy which causes chemical bonds to break, changing the ice to water.;B:The ice releases energy which causes the water molecules to have less kinetic and potential energy, changing their configuration from solid to liquid. C:The ice absorbs energy which causes the water molecules to have more kinetic and potential energy, changing their configuration from a solid to a liquid. D:The ice absorbs energy which causes chemical bonds to break, changing ice to water.

Answers

Answer:

A.

Explanation:

it's needed top release energy due to the breaking of chemical bonds.

Answer:

A: the ice releases energy which causes chemical bonds to break, changing the water to ice.

Explanation:

when a 0.622kg basketbll hits the floor its velocit changes from 4.23m/s down to 3.85m/s up. if the averge force was 72.9N how much time was it in contact with the floor?

Answers

Answer:

Time, t = 3.2 ms

Explanation:

It is given that,

Mass of basketball, m = 0.622 kg

Initial velocity, u = 4.23 m/s

Final velocity, v = 3.85 m/s

Average force acting on the ball, F = 72.9 N

We need to find the time of contact of the ball with the floor. Let t is the time of contact. So,

[tex]F=ma\\\\F=\dfrac{m(v-u)}{t}\\\\t=\dfrac{m(v-u)}{F}\\\\t=\dfrac{0.622\times (3.85-4.23)}{72.9}\\\\t=0.0032\ s\\\\\text{or}\\\\t=3.2\ ms[/tex]

So, the ball is in contact with the floor for 3.2 ms.

A 0.300 kg mass is attached to
a 26.6 N/m spring. It is pulled
0.120 m and released. How much
Kinetic Energy does it have when it
is 0.0600 m from equilibrium?
(Unit = J)

Answers

Answer:

0.144 J

Explanation:

From the question above,

Total elastic energy of the spring = Kinetic energy of the spring + potential energy of the spring

E' = E.k+Ep...................... Equation 1

Ek = E'-Ep......................... Equation 2

Where E' = total elastic energy, E.k = kinetic energy, E.p = potential  energy.

E'  = 1/2ke² = 1/2(26.6)(0.12²) = 0.19152 J.

Ep = 1/2ke² = 1/2(26.6)(0.06²)

Ep = 0.04788 J

Therefore,

Ek = 0.19152-0.04788

Ek = 0.144 J

I just realized my answer was incorrect but I don’t know how to delete an answer.

Please Help!!! I WILL GIVE BRAINLIEST!!!! An electron is in motion at 4.0 × 10^6 m/s horizontally when it enters a region of space between two parallel plates, starting at the negative plate. The electron deflects downwards and strikes the bottom plate. The magnitude of the electric field between the plates is 4.0 x 10^2 N/C and separation between the charged plates is 2.0 cm. a.) Determine the horizontal distance traveled by the electron when it hits the plate. b.)Determine the velocity of the electron as it strikes the plate.

Answers

Answer:

a. 9.52 cm b. 4.34 × 10⁶ m/s

Explanation:

a. The horizontal distance traveled by the electron when it hits the plate.

The electric force F on the electron due to the electric field E of mass, m is

F = -eE = ma

a = -eE/m where a = acceleration of electron

The vertical distance moved by the electron is given by

Δy = ut +1/2at²

u = initial vertical velocity = 0. and take the top plate as y = 0 and bottom plate as y

So,

0 - y = 0 × t + 1/2at²

-y = 1/2at²

substituting a = -eE/m

-y = 1/2(-eE/m)t²

y = eEt²/2m

making t subject of the formula,

t = √(2ym/eE) where t is the time it takes to reach the bottom plate.

Since E = 4.0 × 10² N/C, y = distance between plates = 2.0 cm = 0.02 m, m = 9.109 × 10⁻³¹kg and e = 1.602 × 10⁻¹⁹ C

t = √[(2 × 0.02 m × 9.109 × 10⁻³¹kg)/(1.602 × 10⁻¹⁹ C × 4.0 × 10² N/C)]

t =  √[(0.36436 × 10⁻³¹kgm)/(6.408 × 10⁻¹⁷ N)]

t = √[(0.0569 × 10⁻¹⁴kgm/N)t

t = 0.238 × 10⁻⁷ s

t = 23.8 × 10⁻⁹ s

t = 23.8 ns

The horizontal distance moved when it hits the plates x = vt where v = initial horizontal velocity = 4.0 × 10⁶ m/s

x = 4.0 × 10⁶ m/s × 23.8 × 10⁻⁹ s

= 0.0952 m

= 9.52 cm

b. The velocity of the electron as it strikes the plate.

To find the velocity of the electron as it strikes the plates, we calculate its final vertical velocity V as it strikes the plate. This is gotten from

v' = u + at since u = 0,

v' = at

= -eEt/m

= -(1.602 × 10⁻¹⁹ C × 4.0 × 10² N/C × 0.238 × 10⁻⁷ s)/9.109 × 10⁻³¹kg

= -1.525 × 10⁻²⁴ Ns/9.109 × 10⁻³¹kg

= -0.167 × 10⁷ m/s

= -1.67 × 10⁶ m/s

So, the resultant velocity as it strikes the plate v = √(v'² + v²)

= √((-1.67 × 10⁶ m/s)² + (4 × 10⁶ m/s)²)

= √(2.7889  + 16) × 10⁶ m/s

= √18.7889 × 10⁶ m/s

= 4.335 × 10⁶ m/s

≅ 4.34 × 10⁶ m/s

3. A force of 200 N is applied to an object of area 2 sq.m . the pressure will be

Answers

Answer: 100 Pa

Explanation:

P = F / A = 200/ 2 = 100 Pa

Answer:

100 Pa

Explanation:

Pressure = Force/Area

P = 200/2

P = 100

The SI unit is Pa for pressure, one newton per square meter N/m².

What does FAI stand for?

Answers

Answer:

Femoroacetabular impingement

It occurs when an area of your hip joint becomes pinched when you move in certain directions. :)

What is the momentum of a 35.0 kg cannonball fired from a cannon with a velocity of 500.0 m/s?

Answers

Answer:

p =  17500 kg*m/s

Explanation:

p = mv

p = 35.0 kg * 500.0 m/s = 17500 kg*m/s

The momentum of a 35.0 kg cannonball fired from a cannon with a velocity of 500.0 m/s will be equal to 17500 [tex]\dfrac{kg.m}{s}[/tex]

What is momentum ?

When any body which is having a mass and is in the motion carry momentum with it.

The formula for finding the momentum of any body is given by

[tex]Momentum = Mass\times Velocity[/tex]

Given that-

[tex]Mass = 35 kg[/tex]

[tex]Velocity = 500[/tex]  [tex]\dfrac{m}{s}[/tex]

[tex]Momentum = 35\times500[/tex]

[tex]momentum= 17500 \dfrac{kg.m}{s}[/tex]

Hence The momentum of a 35.0 kg cannonball fired from a cannon with a velocity of 500.0 m/s will be equal to 17500 [tex]\dfrac{kg.m}{s}[/tex]

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