A box of books weighing 319 N is shoved across the floor by a force of 485 N exerted downward at an angle of 35 degres below the horizontal.a) If the coeficent of friction between the box and the floor is 0.57, how long does it take to move the box 4 meters, starting from rest?b) If If the coeficent of friction between the box and the floor is 0.75, how long does it take to move the box 4 meters, starting from rest?

Answer:

false ..........false

Answer:

FALSE                                            

Explanation:

Answer:

ill get back to this question once i find the answer to it

Answer:

0.1875 m/s leftward

Explanation:

Taking rightwards as positive

We are given:

Ball 1:

Mass (m1) = 1.5 kg

velocity (u1) = 2 m/s

Ball 2:

Mass (m2) = 2.5 kg

velocity (u2) = -1.5 m/s          [negative because it is in the opposite direction]

Speed and Direction of Ball 2:

We are told that the balls stick together after the collision

We can say that the balls have the same velocity since they are sticking together

So, Final velocity of Ball 1 (v1) = Final velocity of Ball 2 (v2) = V m/s

According to the law of conservation of momentum

m1u1 + m2u2 = m1v1 + m2v2

replacing the variables

1.5(2) + (2.5)(-1.5) = V (1.5 + 2.5)                     [v1 = v2 = V]

3 + (-3.75) = 4V

-0.75 = 4V

V = -0.75/4                                                    [dividing both sides by 4]

V = -0.1875 m/s

Hence, the balls will move at a velocity of 0.1875 m/s in the Leftward direction

Answer:

V = 6.65 [volt]

Explanation:

First, we must calculate the power by means of the following equation, where the voltage is related to the energy produced or consumed in a given time.

[tex]P=E/t\\P = 40/30\\P = 1.33[s][/tex]

Using the power we can calculate the voltage, by means of the following equation that relates the voltage to the current.

[tex]P=V*I[/tex]

where:

V = voltage [Volts]

I = current = 200 [mA] = 0.2 [A]

[tex]V = 1.33/0.2\\V = 6.65 [volt][/tex]

Answer:

describe, explain, predict, and change/control behavior.

Explanation:

describe: What are they doing? -Pavlov noticed that dogs were salivating when they would see his lab assistant before food was presented to them. This observation acted as a description of what was happening to them.

explain: Why are they doing that?- Pavlov started to look into why they were doing it. There was a stimulus, the assistant giving them food in the past to where they started to salivate at the sight of the lab assistant

predict: What would happen if I responded in this way?- Pavlov predicted that he could get the same reaction if he used a bell as a stimulus. Using this he was able to condition dogs to salivate at the ring of the bell.

change/control: What can I do to get them to stop doing that? Because of this discovery we can use conditioning today. For example, in the classroom teachers can use conditioning with their students to make it easier, parents to teach their children right from wrong and to have good behavior. (you do this bad thing you get time out, do a good thing and I will praise you, etc) It can be used when training employees and many other places.

Answer:

Theory

Explanation:

Theory is a term that is used often in academic work or scientific research to explain certain things or conditions established on universal principles or laws.

It is used to describe the "why and how" or the reason behind the occurrence of a situation.

Hence, it is correct to conclude that THEORY is "an explanation of the relationships among particular phenomena."

Answer:

E) Theory

Explanation:

Edge 2020

Brainliest?

Answer:

3.125 meters.

Explanation:

(3.0*10^8)/(96*10^6)

= 3.125 meters.

Hope this helped!

Answer:

[tex]\displaystyle x=10\sqrt{3}\ m/s[/tex]

[tex]y=10\ m/s[/tex]

Explanation:

Rectangular coordinates of vectors in 2D

Given a vector with a magnitude v and angle θ with respect to the positive horizontal direction, the x and y components of the vector are given by:

[tex]x=v\cos\theta[/tex]

[tex]y=v\sin\theta[/tex]

The soccer ball is kicked upward at an angle θ = 30° and at a speed v=20 m/s.

The rectangular components of the vector are:

[tex]x=20\cos 30^\circ[/tex]

[tex]\displaystyle x=20\cdot \frac{\sqrt{3}}{2}[/tex]

Operating:

[tex]\mathbf{\displaystyle x=10\sqrt{3}\ m/s}[/tex]

[tex]y=20\sin 30^\circ[/tex]

[tex]\displaystyle y=20\cdot \frac{1}{2}[/tex]

Operating:

[tex]\mathbf{y=10\ m/s}[/tex]

Answer:

horizontal component=fcostita

=150cos60

use calculator to evaluate it

for vertical=fsintita

=150sin60

Answer:

5×10^4Pa

Explanation:

Given force of 108 lb is required to pull the lid off the box,

To convert "Ib"to Newton ,we use conversation rate below

1 pounds = 4.4482216282509 newtons

Then 108 lb=x Newton

Cross multiply we have

X= 480.41Newton

The force that is needed to open the lid is F and pressure P.

We know that Pressure= Force/Area

Area is given as 80.0 cm^2, we can convert to m^2 for unit consistency since 1cm^2= 0.001m^2 then

80.0 cm^2 = 80×10^-4m^2

Substitute to the equation of the pressure we have

P= 480.41Newton/(80×10^4m^2)

P=6×10^4 Pa

The pressure in the box will be difference between the initial pressure and final pressure

=( 1.01 ×10^5 Pa)-(6×10^4 Pa)

= 50100Pa

= 5×10^4Pa

Therefore, The pressure in the box was

5×10^4Pa

Answer:

[tex]v=\sqrt{26}~m/s[/tex]

Explanation:

Parametric Equation of the Velocity

Given the position of the particle at any time t as

[tex]r(t) = (x(t),y(t))[/tex]

The instantaneous velocity is the first derivative of the position:

[tex]v(t)=(v_x(t),v_y(t))=(x'(t),y'(t))[/tex]

The speed can be calculated as the magnitude of the velocity:

[tex]v=\sqrt{v_x^2+v_y^2}[/tex]

We are given the coordinates of the position of a particle as:

[tex]x=5t-3t^2[/tex]

[tex]y=5t[/tex]

The coordinates of the velocity are:

[tex]v_x(t)=(5t-3t^2)'=5-6t[/tex]

[tex]v_y(t)=(5t)'=5[/tex]

Evaluating at t=1 s:

[tex]v_x(1)=5-6(1)=-1[/tex]

[tex]v_y(1)=5[/tex]

The velocity is:

[tex]v=\sqrt{(-1)^2+5^2}[/tex]

[tex]v=\sqrt{1+25}[/tex]

[tex]\mathbf{v=\sqrt{26}~m/s}[/tex]

Answer:

e. none of these

Explanation:

An object in FREE-FALL on the MOON would experience only acceleration

Answer:

10778292789403987593790

Explanation:

I am a Cow'

Answer:

Ek = 196.2 [J]

Explanation:

The question concerns the KE kinetic energy.

That is, we must find the kinetic energy at the moment the cannon is fired and the kinetic energy of when the ball hits the ground after having fallen 20 meters.

At the moment when the ball is fired it is 20 meters above ground level. If the ground level is taken as the reference level of potential energy, where it is equal to zero, in this way when the ball is at the highest (20 meters) you have the maximum potential energy.

In this way, the energy in the initial state is equal to the sum of the kinetic energy plus the potential energy. As the energy is conserved this same energy will be present when the ball hits the ground, where the potential energy is zero and will have only kinetic energy.

[tex]E_{1}=E_{2}\\E_{k1}+E_{p1}=E_{k2}\\\frac{1}{2} *m*v^{2} +m*g*h=E_{k2}\\E_{k2}=0.5*1*(5)^{2} +1*9.81*20\\E_{k2}=208.7[J][/tex]

The kinetic energy in the initial state can be easily calculated by means of the following equation.

[tex]E_{k1}=\frac{1}{2} *m*v^{2}\\E_{k1}=0.5*1*(5)^{2}\\E_{k1}=12.5 [J][/tex]

Therefore the change in KE

[tex]E_{k} = 208.7 - 12.5\\E_{k} = 196.2 [J][/tex]

Answer:

Q = PV(In 4)

Explanation:

We are told that the volume expands from V to a state with volume 4V.

Thus, initial volume is V and Final volume is 4V.

We want to find How much heat is added to the expanding gas.

For an isothermal process, the work done is calculated from;

W = nRT(In(V_f/V_i))

Where;

V_f is final volume

V_i is initial volume

Thus;

W = nRT(In(4V/V))

W = nRT(In 4)

Now, from ideal gas equation, we know that;

PV = nRT

Thus;

W = PV(In 4)

Now from first law of thermodynamics, we know that internal energy is zero and thus; Q = W

Where Q is quantity of heat

Thus;

Q = PV(In 4)

Answer:

penis

Explanation:

A spring balance measures the weight of an object by opposing the force of gravity acting with force of an extending spring. May be used to determine mass as well as weight by recalibrating the scale. Some spring balances are available in gram or kilogram markings and are used to measure the mass of an object. Spring balances consist of a cylindrical tube with a spring inside. One end (at the top) is fixed to an adjuster which can be used to calibrate the device. The other end is attached to a hook on which you can hang masses etc.

Answer:

Explanation:

The car’s acceleration can be found by using the formula

[tex]a = \frac{v - u}{t} \\ [/tex]

where

v is the final velocity

u is the initial velocity

t is the time taken

a is the acceleration

From the question we have

[tex]a = \frac{25 - 15}{6} = \frac{10}{6} = \frac{5}{3} \\ = 1.666666...[/tex]

We have the final answer as

Hope this helps you

Answer:

451 milliliters equals 15.25 fluid ounces

Explanation:

The rule of three or is a way of solving problems of proportionality between three known values and an unknown value, establishing a relationship of proportionality between all of them. That is, what is intended with it is to find the fourth term of a proportion knowing the other three.

To solve a direct rule of three, the following formula must be followed:

a ⇒ b

c ⇒ x

So: [tex]x=\frac{c*b}{a}[/tex]

The direct rule of three is the rule applied in this case where there is a change of units.

In this case, the rule of three can be applied in the following way: if there are 29.57 milliliters in 1 fluid ounce, in 451 milliliters how many fluid ounces are there?

[tex]fluid ounces=\frac{451 mL*1 fluid ounce}{29.57 mL}[/tex]

fluid ounces= 15.25

451 milliliters equals 15.25 fluid ounces

Answer:

Potential energy is the energy that is stored in an object. ... When you park your car at the top of a hill, your car has potential energy because the gravity is pulling your car to move downward; if your car's parking brake fails, your vehicle may roll down the hill because of the force of gravity.

Answer:

-20°C

Explanation:

The specific heat capacity of ice using the cgs system is 0.5cal/g°C

The enthalpy change is calculated as follows

ΔH=MC∅ where M represents mass C represents specific heat and ∅ represents the temperature change.

10cal = 2g×0.5cal/g°C×∅

∅=10cal/(2g×0.5cal/g°C)

∅=10°C

Final temperature= -30°C+ 10°C= -20°C

Answer:

-20 degrees Celsius

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Answer:

v = 120 m/s

Explanation:

We are given;

earth's radius; r = 6.37 × 10^(6) m

Angular speed; ω = 2π/(24 × 3600) = 7.27 × 10^(-5) rad/s

Now, we want to find the speed of a point on the earth's surface located at 3/4 of the length of the arc between the equator and the pole, measured from equator.

The angle will be;

θ = ¾ × 90

θ = 67.5

¾ is multiplied by 90° because the angular distance from the pole is 90 degrees.

The speed of a point on the earth's surface located at 3/4 of the length of the arc between the equator and the pole, measured from equator will be:

v = r(cos θ) × ω

v = 6.37 × 10^(6) × cos 67.5 × 7.27 × 10^(-5)

v = 117.22 m/s

Approximation to 2 sig. figures gives;

v = 120 m/s

Answer:

Explanation:

step one:

given data

velocity v=34.2m/s

time t= 8.7s

Step two

Required is the distance the cheetah has covered on the condition

we know that speed= distance/time

make distance subject of formula we have

distance= velocity *time

distance= 34.2*8.7

distance = 297.54m

Therefore the displacement the cheetah covered at that velocity

is 297.54m

Answer:

For any given projector, the width of the image (W) relative to the throw distance (D) is know as the throw ratio D/W or distance over width. So for example, the most common projector throw ratio is 2.0. This means that for each foot of image width, the projector needs to be 2 feet away or D/W = 2/1 = 2.0.

Answer:

Explanation:

Given;

initial velocity of the ball, u = 23 m/s

time of motion, t = 2 s

The position of the ball after 2 s is given by;

h = ut - ¹/₂gt²

h = (23 x 2) - ¹/₂ x 9.8 x 2²

h = 46 - 19.6

h = 26.4 m

The velocity of the ball after 2 s is given by;

v² = u² + 2(-g)h

v² = u² - 2gh

v² = 23² - (2 x 9.8 x 26.4)

v² = 529 - 517.44

v² = 11.56

v = √11.56

v = 3.4 m/s

Answer:

e. 55.0 m

Explanation:

Given;

diameter of the aluminum wire, d = 0.865 mm

radius of the wire, r = d/2 = 0.4325 mm = 0.4325 x 10⁻³ m

resistivity of the wire, ρ = 2.65 x 10⁻⁸ Ω-m

resistance of the wire, R = 2.48 Ω

The resistance of a wire is given by;

[tex]R = \frac{\rho \ L}{A} \\\\[/tex]

where;

L is length of the wire

A is area of the wire = πr² = π(0.4325 x 10⁻³ )² = 5.877 x 10⁻⁷ m²

Substitute the givens and solve for L,

[tex]L = \frac{RA}{\rho} \\\\L = \frac{(2.48)(5.877*10^{-7})}{2.65*10^{-8}}\\\\L = 55.0 \ m[/tex]

Therefore, the length of the wire is 55.0 m

Answer:

The mass of the catfish is 2.13 kg

Explanation:

Period of oscillation, T = 0.19 s

spring constant, k = 2330 N/m

The period of oscillation of the spring is given by;

[tex]T = 2\pi \sqrt{\frac{m}{k} }\\\\\frac{T}{2\pi} = \sqrt{\frac{m}{k} }\\\\\frac{T^2}{4\pi^2} = \frac{m}{k}\\\\m = \frac{kT^2}{4\pi^2}[/tex]

where;

m is mass of the catfish

substitute the given values and solve for m;

[tex]m = \frac{kT^2}{4\pi^2} \\\\m = \frac{(2330)(0.19)^2}{4\pi^2} \\\\m = 2.13 \ kg[/tex]

Therefore, the mass of the catfish is 2.13 kg

Answer:

Specific Gravity = 0.378

Explanation:

First, we will find the force exerted by the can on the table. This force will be equal to the weight of the can:

Pressure = Force/Area = Weight/Area

Weight = Pressure*Area

where,

Area = πdiameter²/4 = π[(3.1 in)(0.0254 m/1 in)]²/4 = 4.8 x 10⁻³ m²

Weight = (510 N/m²)(4.8 x 10⁻³ m²)

Weight = 2.48 N

Now, the weight is given as:

Weight = mg

2.48 N = m(9.8 m/s²)

m = (2.48 N)/(9.8 m/s²)

m = 0.25 kg

Now, we calculate volume of can:

Volume = (Area)(Height) = (4.8 x 10⁻³ m²)(5.42 in)(0.0254 m/1 in)

Volume = 6.6 x 10⁻⁴ m³

Hence, the density of can will be:

Density of Can = m/Volume = 0.25 kg/6.6 x 10⁻⁴ m³

Density of Can = 378.32 kg/m³

So, the specific gravity of Can will be:

Specific Gravity = Density of Can/Density of Water

Specific Gravity = (378.32 kg/m³)/(1000 kg/m³)

Specific Gravity = 0.378

Answer:

320 paper clips

Explanation:

mass = volume × density = 20cm³ × 8g/cm³ = 160g

mass of 1 paper clip = 0.50g

mass of x paper clips = 160g

x = 160/0.50 = 320