s the gravitational force greater between the objects in Pair 1 or Pair 2? Explain why. (Picture shown below)

Complete question is;

Shoveling snow can be extremely taxing since the arms have such a low efficiency in this activity. Suppose a person shoveling a sidewalk metabolizes food at the rate of 800 W. (The efficiency of a person shoveling is 3%.)

(a) What is her useful power output? (b) How long will it take her to lift 3000 kg of snow 1.20 m? (This could be the amount of heavy snow on 20 m of footpath.) (c) How much waste heat transfer in kilojoules will she generate in the process?

Answer:

A) P_out = 24 W

B) t = 1470 s

C) Q = 1140.72 KJ

Explanation:

We are given;

Input Power; P_in = 800 W

Efficiency; η = 3% = 0.03

A) Formula for efficiency is;

η = P_out/P_in

Making P_out the subject, we have;

P_out = η•P_in

P_out = 0.03 × 800

P_out = 24 W

B) We know that;

Power = work done/time taken

Thus;

P_out = mgh/t

We are given;

m = 3000 kg

h = 1.20 m

Thus, time is;

t = (3000 × 9.8 × 1.2)/24

t = 1470 s

C) amount of heat wasted is calculated from;

Q = (P_in - P_out)t

Q = (800 - 24) × 1470

Q = 1,140,720 J

Q = 1140.72 KJ

The release of infrared light from radioactive materials is what demonstrates light possessing wave characteristics.

This is defined as the propagation of disturbances from one place to another in an organized way.

The release of waves in a diffraction pattern is why option C was chosen as the most appropriate choice.

Read more about Wave here https://brainly.com/question/15663649

Answer:

A: Alpha decay.

Explanation:

The transmutation of ²³⁸U is a nuclear reaction that yields ²³⁴Th and an alpha particle.

Now, Alpha decay is a radioactive decay whereby an atomic nucleus emits an alpha particle which then changes into an atom with a mass number that is decreased by four and atomic number decreased by 2.

In this case, mass number is reduced from 238 to 234. Thus, it's an alpha decay.

Answer: I believe hydrogen cyanide, carbon monoxide, and ammonia are the three chemicals involved, but im not sure

Answer:

c.an electron or positron

Answer:

your answer would be c

Explanation:

Answer:

the speed of an object is 9.42 m/s

Explanation:

The computation of the speed of an object is given below:

v = 2πr ÷ t

where

v denotes the speed

r denotes the radius

r denotes the time

So,

= 2 × 3.14 × 0.75 ÷ 0.50

= 9.42 m/s

Hence, the speed of an object is 9.42 m/s

the same would be considered and relevant too

Answer:

B. Attract each other with a force of 10 newtons.

Explanation:

Statement is incorrectly written. The correct form is: A [tex]+10\,\mu C[/tex] charge and a [tex]-10\,\mu C[/tex] at a distance of 0.3 meters.

The two particles have charges opposite to each other, so they attract each other due to electrostatic force, described by Coulomb's Law, whose formula is described below:

[tex]F = \frac{\kappa \cdot |q_{A}|\cdot |q_{B}|}{r^{2}}[/tex] (1)

Where:

[tex]F[/tex] - Electrostatic force, in newtons.

[tex]\kappa[/tex] - Electrostatic constant, in newton-square meters per square coulomb.

[tex]|q_{A}|,|q_{B}|[/tex] - Magnitudes of electric charges, in coulombs.

[tex]r[/tex] - Distance between charges, in meters.

If we know that [tex]\kappa = 8.988\times 10^{9}\,\frac{N\cdot m^{2}}{C^{2}}[/tex], [tex]|q_{A}| = |q_{B}| = 10\times 10^{-6}\,C[/tex] and [tex]r = 0.3\,m[/tex], then the magnitude of the electrostatic force is:

[tex]F = \frac{\kappa \cdot |q_{A}|\cdot |q_{B}|}{r^{2}}[/tex]

[tex]F = 9.987\,N[/tex]

In consequence, correct answer is B.

Solution :

We know that the time period of oscillation of a spring mass system is given by :

[tex]$T = 2 \pi \sqrt{\frac{m}{k}}$[/tex]     , where m is mass and k is the spring constant

∴ [tex]$T_A = 2 \pi \sqrt{\frac{m}{k}}$[/tex]    .........(i)

  [tex]$T_B = 2 \pi \sqrt{\frac{2m}{k}}$[/tex] ..........(ii)

  [tex]$T_C = 2 \pi \sqrt{\frac{3m}{6k}} = 2 \pi \sqrt{\frac{m}{2k}}$[/tex]   ..........(iii)

  [tex]$T_D = 2 \pi \sqrt{\frac{m}{4k}}$[/tex]   ...............(iv)

Comparing the equations (i), (ii), (iii) and (iv)

We get

[tex]$T_B > T_A > T_C > T_D$[/tex]

So in increasing order of time period, we get

[tex]$T_D < T_C < T_A < T_B$[/tex]

Answer:

a) [tex](v_1)=0.3989m/s[/tex]

b) [tex]\theta_1=80.5 \textdegree[/tex]

c) [tex]K.E=0.036J[/tex]

Explanation:

From the question we are told that:

Initial speed of 1st ball [tex]u_{1}=0 m/s[/tex]

Mass of 1st ball [tex]m_1=0.585kg[/tex]

Mass of 2nd ball [tex]m_2=0.420kg[/tex]

Initial speed of 2nd ball [tex]u_{2}=0.270 m/s[/tex]

Final speed of 2nd ball [tex]v_{2}=0.220 m/s[/tex]

Angle of collision [tex]\angle=36.9 \textdegree[/tex]

a)

Generally the equation for law of conservation is mathematically given by

[tex]m_1u_1+m_2u_2=m_1v_1^2+m_2v_2^2[/tex]

The final velocity [tex]v_1[/tex] is given as

[tex]0+(0.420)(0.270)=(0.585)(v_1)^2+(0.420)(0.220)^2[/tex]

[tex](v_1)^2=\frac{(0.420)(0.270)-(0.420)(0.220)^2}{0.585}[/tex]

[tex](v_1)^2=0.1591[/tex]

[tex](v_1)=0.3989m/s[/tex]

b)

Generally the equation for law of conservation is mathematically given by

[tex]m_1u_1+m_2u_2=m_1v_1cos\theta_1+m_2\theta_2[/tex]

[tex]0+(0.420)(0.270)=(0.585)(1.511)cos\theta_1+(0.420)(0.220)cos36 \textdegree[/tex]

[tex]cos\theta_1= \frac{(0.420)(0.270)-(0.420)(0.220)cos36 \textdegree}{(0.585)(0.3989)}[/tex]

[tex]cos\theta_1=0.1656[/tex]

[tex]\theta_1=80.5 \textdegree[/tex]

c)

Generally the equation for kinetic energy is mathematically given by

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

1st Ball

[tex]K.E=\frac{1}{2} (0.585)(0.3989)^2[/tex]

[tex]K.E=0.0465J[/tex]

2nd ball

[tex]K.E=\frac{1}{2} (0.420)(0.220)^2[/tex]

[tex]K.E=0.101J[/tex]

Therefore the  change in the total kinetic energy of the two balls as a result of the collision is

[tex]0.101-0.0465[/tex]

[tex]K.E=0.036J[/tex]

Answer:

Either heat added or mechanical work done.

Explanation:

Since he found stirring rod on the desk and a cigarette lighter. This means that the beaker was probably either heated with the aid of fire from the lighter.

Also, the stirring rod could have been used to stir the water which will increase the kinetic energy which also means an increase in temperature.

Thus, it's either heat was added or mechanical work was done as a result of stirring.

Answer:

Explanation:

Given the following data;

Mass = 9.1 X 10^{-31} kg

Velocity = 4.8x10⁵ m/s

Planck’s constant ( h ) = 6.6262 * 10^{-34}

To find the wavelength;

Applying de broglie's equation;

Wavelength = h/mv

Wavelength = ) = 6.6262 * 10^{-34}/(9.1 X 10^{-31} * 4.8x10⁵)

Wavelength = 1.52 * 10^{-71} meters

Explanation:

V= Current × Resistance

V= 400mA × 5kohms

V= 2000V

Answer:

g = 11.2 m/s²

Explanation:

First, we will calculate the time period of the pendulum:

[tex]T = \frac{t}{n}[/tex]

where,

T = Time period = ?

t = time taken = 135 s

n = no. of swings in given time = 98

Therefore,

[tex]T = \frac{135\ s}{98}[/tex]

T = 1.38 s

Now, we utilize the second formula for the time period of the simple pendulum, given as follows:

[tex]T = 2\pi \sqrt{\frac{l}{g}}[/tex]

where,

l = length of pendulum = 54 cm = 0.54 m

g = acceleration due to gravity on the planet = ?

Therefore,

[tex](1.38\ s)^2 = 4\pi^2(\frac{0.54\ m}{g} )\\\\g = \frac{4\pi^2(0.54\ m)}{(1.38\ s)^2}[/tex]

g = 11.2 m/s²

Answer moderate alcohol can be good for you health

Explanation: but I wouldn't do none of those things to be honest

SMARTEST

Answer:

none of the above

Explanation:

its an easy question haha

Answer:

$1.26

Explanation:

Power =energy/ time

energy =powerxtime

energy =50x31x24=37200

=37.2kwh

1kwh =3.39

37.2kwh=3.39x37.2=126.108cent

=$1.26

Answer:

250w

Explanation:

W=Fd

W= 250 x 4= 1000J

P=E/t=1000/4s=250w

Answer: True!

Explanation: The force is proportional to the square of the distance between 2 point masses

The moment of inertia of Pulley is 8.89 kgm².

The angular acceleration of the pulley is calculated as follows;

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

where;

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]

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

Answer:

[tex]T_d=2.8*10^-^6\%[/tex]

Explanation:

From the question we are told that

Distance b/w Earth and the moon [tex]d_e=3.84×10^8 m[/tex]

Thickness of Earth's atmosphere[tex]d_t=30km[/tex]

Constant index of refraction [tex]n = 1.000293.[/tex]

Generally the equation for percentage of time delay [tex]T_d[/tex] is mathematically given as

[tex]T_d=\frac{d(n-1)}{rm}*100\%[/tex]

[tex]T_d=\frac{(35*10^3)(1.000293-1)()100)}{3.674*10^8} *\%[/tex]

[tex]T_d=2.8*10^-^6 \%[/tex]

Therefore the general percentage correction needed because of tym deley is given as

[tex]T_d=2.8*10^-^6\%[/tex]

Answer:

the current INCREASES.

Explanation:

In this experiment, the electrons are generated by a filament with very low speed, when they are subjected to a difference and potential ΔV they acquire the necessary speed to reach the regulation and the current can be measured.

Some electrons collide elastically with the atoms of the mercury gas that is much heavier and are scattered in any direction, so they do not reach the grid, by increasing the voltage this scattered electrons can acquire the necessary speed in the direction of grid to reach it and therefore are also measured, increasing the current.

Therefore, as the power difference increases, the current INCREASES.

Answer:

Explanation:

they trade velocities... so the Satellite now is going 5000 m/s  

Answer:

The work done will be "763 J". A further explanation is given below.

Explanation:

The given values are:

[tex]Q_1=1000 \ J[/tex]

Temperature,

[tex]T_1=900^{\circ} C[/tex]

i.e,

    [tex]=1173[/tex]

[tex]T_2=5^{\circ}C[/tex]

i.e.,

    [tex]=278[/tex]

As we know,

⇒  [tex]\eta =1-\frac{T_2}{T_1}[/tex]

On substituting the values, we get

⇒     [tex]=1-\frac{278}{1173}[/tex]

⇒     [tex]=\frac{1173-278}{1173}[/tex]

⇒     [tex]=\frac{895}{1173}[/tex]

⇒     [tex]=0.763[/tex]

then,

⇒  [tex]W=\eta Q_1[/tex]

⇒       [tex]=0.763\times 1000[/tex]

⇒       [tex]=763 \ J[/tex]

Answer:

One degree unit on the Celcius scale is equivalent to one degree unit on the kelvin scale. The only difference between these two scales is the zero point. The zero point on the Celcius scale was defined as the freezing point of water, which means that there are higher and lower temperatures around it.

Answer:

a. E = 900000 J = 900 KJ

b. ΔT = 8.18 °C

c. Cost = $ 7.2  

Explanation:

a.

The energy can be given by:

[tex]E = Pt[/tex]

where,

E = Energy = ?

P = Power = 500 W

t = time = (0.5 h)(3600 s/1 h) = 1800 s

Therefore,

[tex]E = (500\ W)(1800\ s)[/tex]

E = 900000 J = 900 KJ

b.

The change in temperature of room air is given by the following formula:

[tex]0.5E = mC\Delta T\\[/tex]   (since 50% of energy is used to heat air)

where,

m = mass of air = 50 kg

C = specific heat of air = 1.1 KJ/kg.°C

ΔT = Change in temperature of air = ?

Therefore,

[tex](0.5)(900\ KJ) = (50\ kg)(1.1\ KJ/Kg.^oC)\Delta T[/tex]

ΔT = 8.18 °C

c.

First, we will calculate the total energy consumed:

[tex]E = (0.5\ KW)(6\ h/d)(30\ d)\\E = 90\ KWh[/tex]

Now, for the cost:

[tex]Cost = (Unit\ Cost)(Energy)\\Cost = (\$ 0.08\KWh)(90\ KWh)[/tex]

Cost = $ 7.2

Answer:

32km per hour

Explanation:

Explanation:

In first case v = a t

==> a t = 40 km p h

Now distance covered S1 + S2 + S3

S1 = 1/2 a t^2 and S3 = 1/2 a t^2

But S2 = 3t * 40 = 120 t km

Hence total distance = at^2 + 120 t

Time taken (total) = t + 3t + t = 5 t

Hence average speed = at^2 + 120 t / 5 t

Cancelling t we have at + 120 / 5 = 40 + 120 / 5 = 160/5 = 32 km per hour

Answer:

Let's see the similarities between the two forces

* are proportional to the product of a magnitude, mass or charge

* They are inversely proportional to the square of the distance

* They are long-range forces since zero is not made up to an infinite distance. The gravitational force is always attractive, the electrical force can be attractive or repulsive.

The differences in them

* The electric force in much greater than the gravitational force

* The gravitational force is always attractive, the electrical force can be attractive or repulsive.

Explanation:

Let's start by calculating each force.

Gravitational force

             F =[tex]G \frac{m_1m_2}{r^2}[/tex]  

let's calculate

             F = 6.67 10⁻¹¹  1  1 / 1²

             F = 6.67 10⁻¹¹ N

Electric force

             F = [tex]k \frac{q_1q_2}{r^2}[/tex]  

indicates that the charge is q = 10 C

            F = 9 10⁹ 10 10 / 1²

            F = 9 10¹¹ N

Let's see the similarities between the two forces

* are proportional to the product of a magnitude, mass or charge

* They are inversely proportional to the square of the distance

* They are long-range forces since zero is not made up to an infinite distance. The gravitational force is always attractive, the electrical force can be attractive or repulsive.

The differences in them

* The electric force in much greater than the gravitational force

* The gravitational force is always attractive, the electrical force can be attractive or repulsive.

Answer:

The amount of energy carried by a wave is related to the amplitude of the wave

Explanation:

A high energy wave is characterized by a high amplitude; a low energy wave is characterized by a low amplitude.  The energy imparted to a pulse will only affect the amplitude of that pulse.

Hope this helped!!!

Answer:

1.33

Explanation:

For an optical instrument, the magnification ratio of the apparent diameter of the image to that of the object.

Mathematically, from the given information;

Magnification[tex]= \dfrac{n_{water}}{n_{air}}[/tex]

where;

[tex]n_{water} =1.33\\ \\ n_{air} = 1.00[/tex]

[tex]= \dfrac{1.33}{1.00} \\ \\= \mathbf{1.33}[/tex]