A boat takes off from the dock at 2.5m/s and speeds up at 4.2m/s2 for 6.0 seconds how far has the boat traveled

Answer:

a) 70, 95

b) 95-70= 25cc

c) density= mass/volume

102/25

=4.08g/cc

Answer:

θ = 66º

Explanation:

This exercise of Newton's second law must be solved in part, let's start by finding the slowing down acceleration of the ball

           a = v² / r

the radius of the circle is

          sin θ = r / L

          r = L sin θ

we substitute

          a = v² /L sin θ

now let's write Newton's second law

vertical axis

            T_y -W = 0

             T_y = W

radial axis

            Tₓ = m a                 (1)

let's use trigonometry for the components of the string tension

             cos θ = T_y / T

             sin θ = Tₓ / T

             Tₓ = T sin θ

we substitute in 1

            T sin θ = [tex]\frac{m \ v^2}{L \ sin \theta}[/tex]

             T L sin² θ = m v²

we write our system of equations

             T cos θ  = m g

             T L sin ² tea = m v²

we divide the two equations

             L [tex]\frac{sin^2 \theta}{cos \theta}[/tex] = v² / g

             (1 -cos²)/ cos θ  = [tex]\frac{v^2 }{g \ L}[/tex]

             1 - cos² θ  =  [tex]\frac{4.75^2}{9.81 \ 2.37}[/tex]   cos θ

             cos² θ + 0.97044 cos θ -1   = 0

we change variable    cos  θ = x

             x² + 0.97044 x - 1 =0

             x= [tex]\frac{-0.97 \pm \sqrt{0.97^2 - 4 1} }{2}[/tex]

           since the square root is imaginary there is no real solution to the problem, suppose that the radius is 1 m r = 1 m

           T sin θ = [tex]\frac{m \ v^2}{ r}[/tex]

           T cos θ  = m g

resolved

           tan θ =  [tex]\frac{v^2}{ r g}[/tex]

           θ = tan⁻¹ ( 4.75²/ 1 9.81)

           θ = 66º

Answer:

1. The efficiency of the radiator is 90 %

2. The efficiency of the torch is 65 %

3. The efficiency of the car is 40 %

4. The efficiency of the energy saver is 70 %

5. The efficiency of the speaker is 50 %

Explanation:

Efficiency = (Useful energy out ÷ Total energy in) × 100 J

1. Useful energy = 900 J

The total energy in = 1000 J

The efficiency of the radiator = ((900 J)/(1,000 J)) × 100 % = 90 %

2. Useful energy = 65 J

The total energy in = 100 J

The efficiency of the torch = ((65 J)/(100 J)) × 100 % = 65 %

3. Useful energy = 4,000 J

The total energy in = 10,000 J

The efficiency of the car = ((4,000 J)/(10,000 J)) × 100 % = 40 %

4. Useful energy = 700 J

The total energy in = 1,000 J

The efficiency of the energy saver = ((700 J)/(1,000 J)) × 100 % = 70 %

5. Useful energy = 50 J

The total energy in = 100 J

The efficiency of the speaker = ((50 J)/(100 J)) × 100 % = 50 %

Answer:

The capacity of an RD bottle is 100cc and its mass is 45g. Find the mass of the bottle when it is filled with a liquid of density 600kg/[tex]m^{3}[/tex]

EXPLANATION:

100cc=100[tex]cm^{3}[/tex]

density of liquid=600Kg/  =0.6gm/

 so mass of 100cc liquid will be m=d×V=0.6×100=60gm

So mass of bottle filled with liquid will be bottle+liquid=45gm+60gm=105gm  

Answer is 105gm.

Answer:

The mass of platinum iridium rod whose diameter and height are equal an kept at international bureau of weight and measurement in Paris of France is called as one standard kg.

Answer:

Joule

Explanation:

the unit of work is Joule determined by the letter J.

Answer:

Explanation:

Joule is defined as the work done by a force of one newton causing a displacement of one meter. Sometimes, newton-metre (N-m) is also used for measuring work.

Answer:

DU = 120 Joules

Explanation:

Given the following data;

Quantity of energy = 200 J

Work = 80 J

To find the change in internal energy;

Mathematically, the change in internal energy of a system is given by the formula;

DU = Q - W

Where;

DU is the change in internal energy.

Q is the quantity of energy.

W is the work done.

Substituting into the formula, we have;

DU = 200 - 80

DU = 120 Joules

We know

[tex]\boxed{\sf K.E=\dfrac{1}{2}mv^2}[/tex]

[tex]\\ \sf\longmapsto K.E=\dfrac{1}{2}\times 2\times 40^2[/tex]

[tex]\\ \sf\longmapsto K.E=40^2[/tex]

[tex]\\ \sf\longmapsto K.E=1600J[/tex]

Answer:

C

Explanation:

Answer:

A)

Explanation:

it keeps the electric current flowing in one direction

Answer:

Explanation:

                    The right side of your heart receives oxygen-poor blood from your veins and pumps it to your lungs, where it picks up oxygen and gets rid of carbon dioxide. The left side of your heart receives oxygen-rich blood from your lungs and pumps it through your arteries to the rest of your body.

        #I AM ILLITERATE

Answer:

Their final relative velocity is 0.190 m/s

Explanation:

The relative velocity of the satellites, v = 0.190 m/s

The mass of the first satellite, m₁ = 4.00 × 10³ kg

The mass of the second satellite, m₂ = 7.50 × 10³ kg

Given that the satellites have elastic collision, we have;

[tex]v_2 = \dfrac{2 \cdot m_1}{m_1 + m_2} \cdot u_1 - \dfrac{m_1 - m_2}{m_1 + m_2} \cdot u_2[/tex]

[tex]v_2 = \dfrac{ m_1 - m_2}{m_1 + m_2} \cdot u_1 + \dfrac{2 \cdot m_2}{m_1 + m_2} \cdot u_2[/tex]

Given that the initial velocities are equal in magnitude, we have;

u₁ = u₂ = v/2

u₁ = u₂ = 0.190 m/s/2 = 0.095 m/s

v₁ and v₂ = The final velocities of the satellites

We get;

[tex]v_1 = \dfrac{2 \times 4.0 \times 10^3}{4.0 \times 10^3 + 7.50 \times 10^3} \times 0.095 - \dfrac{4.0 \times 10^3- 7.50\times 10^3}{4.0 \times 10^3+ 7.50\times 10^3} \times 0.095 = 0.095[/tex]

[tex]v_2 = \dfrac{ 4.0 \times 10^3 - 7.50\times 10^3}{4.0 \times 10^3 + 7.50 \times 10^3} \times 0.095 + \dfrac{2 \times 7.50\times 10^3}{4.0 \times 10^3+ 7.50\times 10^3} \times 0.095 = 0.095[/tex]

The final relative velocity of the satellite, [tex]v_f[/tex] = v₁ + v₂

∴ [tex]v_f[/tex] = 0.095 + 0.095 = 0.190

The final relative velocity of the satellite, [tex]v_f[/tex] = 0.190 m/s

Answer:

Answer:

Yes but no

Explanation:

Here the kid cant say that he has created s magnetic field as iron fillings do not have magnetic properties

Answer:  An effect of continental drift is causing tectonic plates resting upon the convecting mantle to move which results in natural disasters like earthquakes, volcanic eruptions, and more.

[tex]\\ \sf\longmapsto P.E=mgh[/tex]

[tex]\\ \sf\longmapsto P.E=150(2)(10)[/tex]

[tex]\\ \sf\longmapsto P.E=3000J[/tex]

In 2nd case

[tex]\\ \sf\longmapsto P.E=200(2)(10)[/tex]

[tex]\\ \sf\longmapsto P.E=4000J[/tex]

We can observe that

Answer:

SI unit is an internationally accepted system and have the same value all over the world .

I don't know the importance sotry

Answer:

SI unit is an internationally accepted system that have same value all over the world.

Answer:

Explanation:

As seen, batteries have chemical energy in them stored which when used in any electronics produces electricity.

Thus, we can conclude that a battery converts chemical energy into electric energy.

Answer:

Velocity is the rate of change of displacement.

Answer:

acceleration = v-u/ t

= 15-10/5

= 5/5

= 1 m/s2

Explanation:

hope this helped you.

Answer:

[tex]\boxed {\boxed {\sf 1 \ m/s^2}}[/tex]

Explanation:

Acceleration is the change in velocity over the change in time. Therefore, the formula for calculating acceleration is:

[tex]a= \frac{v_f-v_i}{t}[/tex]

Since the body's velocity increased from 10 meters per second to 15 meters per second 15 m/s is the final velocity and 10 m/s is the initial velocity. The time is 5 seconds.

[tex]a= \frac{ 15 \ m/s - 10 \ m/s}{5 \ s}[/tex]

Solve the numerator.

[tex]a= \frac{ 5 \ m/s }{5 \ s}[/tex]

Divide.

[tex]a= 1 \ m/s/s[/tex]

[tex]a= 1 m/s^2[/tex]

The acceleration is 1 meter per second squared.

Answer:

Pressure and velocity are inversely proportional to each other because if pressure increase, the velocity decrease to keep the algebraic sum of potential energy, kinetic energy and pressure constant.

The answer to the digits rounded to one significant figure is 100.

Significant figures are the most important figures in a number of digits.

The closer a digit is to the beginning of a number, the more important  or significant  it is.

But, the rule for rounding up a set of numbers to the first significant or to one significant figure is that:

From the numbers 98.907, 9 is the most significant digit followed by 8.

8 is greater than 5 so we should round up by adding one to 9 making the number 100.

learn more here:

https://brainly.com/question/11566364

Assuming the applied force is exerted parallel to the floor, by Newton's second law both the net vertical and net horizontal forces would be zero:

∑ F (horizontal) = p - f = 0 … … … because the desk is pushed at a constant speed

∑ F (vertical) = n - mg = 0 … … … because the desk doesn't move up or down

where p is the magnitude of the applied force, f is the mag. of kinetic friction, n is the mag. of the normal force due to contact between the floor and desk, and mg is the weight of the desk. We have

n = mg = (100 kg) g = 980 N

and the mag. of friction is proportional to n according to

f = 0.4 n = 392 N

Then the applied force p has magnitude

p = f = 392 N

Answer:

It is the inability of the body to change by itself its state of rest or uniform motion or direction. Types of Inertia- It is of three types-(1)Inertia of rest (2) Inertia of motion(3) Inertia of direction. (1) Inertia of rest - It is the inability of the body to change by itself its state if rest.

Answer:

Kepler's laws apply: First Law: Planetary orbits are elliptical with the sun at a focus. Second Law: The radius vector from the sun to a planet sweeps equal areas in equal times. Third Law: The ratio of the square of the period of revolution and the cube of the ellipse semimajor axis is the same for all planets.

Answer:

A) The population of prey is greater than that of predator

Answer:

5.0cm

Explanation:

To get the height of the image, we will use the magnification formula as shown:

m = Hi/H = v/u

Hi is the image height

H is the object height

v is the image distance

u is the object distance

First, we need to get the image distance v

Using the mirror formula;

1/f = 1/v+ 1/u

1/-6 = 1/v + 1/12

1/v = -1/12 - 1/6

1/v = -1-2/12

1/v = -3/12

v = 12/-3cm

v = -4cm

Next is to get the image height Hi

Using the expression;

Hi/H = v/u

Hi/15 = 4/12

Hi/15 = 1/3

3Hi = 15

Hi = 15/3

Hi = 5.0cm

Hence the image height is 5.0cm

Answer:

D. 5.0 cm

Explanation:

got it correct on the test

Answer:

The comparison of unknown quantity with known quantity is called measurement

Answer:

the size, length or amount of something is a measurement.

Explanation:

Measurements help in daily life and are important to development, accuracy and making decisions.

Answer:V₁=300ml

T₁=27°C

V₂=?

T₂= -3°C

as we know

V₁T₁=V₂T₂

By putting values in formula

300ml×27°C=V₂×(-3°C)

300ml×27°C/-3°C=V₂

8100ml/-3=V₂

-2700ml=V₂

or V₂=  -2700ml

Answer:

The height of the wave is determined by the wind strength and fetch.

Explanation:

The height of the wave is determined by the wind strength and fetch.

The more the strength and the more the fetch size the more will be the height of the wave.

Remember as the wave approaches the coast its wavelength decreases and the wave height increases, whereas when the wave goes away from the coast its wavelength increases and height decreases.

Answer:

A dicot is a flowering plant that has one seed leaves. The monocot plants have a single cotyledon. Maize only has one cotyledon in their seed, so it's a monocot. Seeds having two Cotyles are mainly called a Dicot. A pea is a dicotyledonous plant, the seed (the pea itself) has two halves, cotyledons, hence dicot being 2.

Explanation:

One or more of the cotyledons are the first to appear from a germinating seed. Based on the number of cotyledons, botanists classify flowering plants (angiosperms) into :

a) plants with one embryonic leaf, termed monocotyledonous (monocots).

b) plants with two embryonic leaves, termed dicotyledonous (dicots).

Helpful Link:

https://www.vedantu.com/question-answer/in-pea-caster-and-maize-the-number-of-cotyledons-class-11-biology-cbse-5f626a17e5bde9062ff6d2a3