70kg man runs up a flight of staurs in 4 sec . The vertical height of the stairs is 4.5 m . Calculate his power

Answer:

a) tangent ; b) 153.88 yds ; c) No , less than or equal to 45° ; D) 45°

Explanation:

Given the following ;

From the triangle sketch :

Base length = 50 yards

Angle of elevation = 72°

a. Which trigonometric ratio would you use to calculate how high the blimp will be above the 50 yard line?

Using trigonometry :

The height of the blimp will be calculated using :

Tangent :

Tan θ = opposite / Adjacent

B.) How high above the ground is the blimp?

Using :

Tan θ = opposite / Adjacent

Θ = 72° ; adjacent = 52, opposite = height(h)

Tan 72° = h / 50

h = 3.0776835 * 50

h = 153.88 yds

C.) In order to be able to read the advertisement on the side of the blimp the highest the blimp can be is 150 feet. Will the fans be able to read the advertisement?

1 yard = 3 Feets

153.88 yards = 3 * 153.88

= 461.65 feets

No, because the height of the blimp is 461.65 Feets which is greater than 150 Feets.

To make viewing possible, the angle of elevation should be:

50 yards is equivalent to (3 * 50) = 150 feets

Max imum Height of blimp = 150 Feets

From pythagoras ;

Tanθ = 150 Feets / 150 Feets

Tanθ = 1

θ = tan^-1(1)

θ = 45°

To make viewing advertisement possible, angle of elevation should not exceed 45°

d.)If height of blimp is 150 Feets, then the exact angle of elevation will be 45°

Answer:

The work done by Joel is greater than the work done by Jerry.

Explanation:

Let suppose that forces are parallel or antiparallel to the direction of motion. Given that Joel and Jerry exert constant forces on the object, the definition of work can be simplified as:

[tex]W = F\cdot \Delta s[/tex]

Where:

[tex]W[/tex] - Work, measured in joules.

[tex]F[/tex] - Force exerted on the object, measured in newtons.

[tex]\Delta s[/tex] - Travelled distance by the object, measured in meters.

During the first 10 minutes, the net work exerted on the object is zero. That is:

[tex]W_{net} = W_{Joel} - W_{Jerry}[/tex]

[tex]W_{net} = F\cdot \Delta s - F\cdot \Delta s[/tex]

[tex]W_{net} = (F-F)\cdot \Delta s[/tex]

[tex]W_{net} = 0\cdot \Delta s[/tex]

[tex]W_{net} = 0\,J[/tex]

In exchange, the net work in the next 5 minutes is the work done by Joel on the object:

[tex]W_{net} = W_{Joel}[/tex]

[tex]W_{net} = F\cdot \Delta s[/tex]

Hence, the work done by Joel is greater than the work done by Jerry.

Answer:

i. the wavelength is 7.2 m

ii. the wavelength is 2.4 m

Explanation:

the wavelength of a wave is from crest to crest or from trough to trough.

Answer:

two of them in series with one in parallel

Explanation:

When two or more batteries are connected in

(a) series: the total voltage produced is equal to the sum of the voltages on each of the batteries. For example, if two batteries A and B of 3V and 2V respectively are connected in series, then the total voltage produced is

3V + 2V = 5V

(b) parallel: the total voltage produced is equal to the voltage on any one of the batteries. As a mention, only batteries of the same voltage should be connected together in parallel. For example, if two batteries A and B each of 4V are connected together in parallel, then the total voltage produced is 4V.

If these batteries are not of the same voltage, then the one of larger voltage will charge the one of the lower voltage until they both have the same voltage. That means that their eventual voltage will be the average of their voltages. For example, if two batteries A and B of 3V and 2V respectively, are connected in parallel, their total voltage will be,

(3V + 2V) / 2 =2.5V

Now, from the question.

Since there are three cells each of value 2V.

=>If we connect two of them in series, the total voltage from those two cells will be 2V + 2V = 4V

=>If we then connect this series connection in parallel with the third cell, then we have a parallel combination of 4V and 2V. Since they have different voltages, then the total voltage will be the average of the two voltages. i.e

(4V + 2V) / 2 = 6 / 2 = 3V

Therefore, to have a total of 3V from three cells each of 2V, we need to connect two of them in series with one in parallel

Answer:

Yes great job it was well written!:)

Answer:

The material will still remain afloat.

Explanation:

The fact that the material floated on water as a solid piece means that the material is less dense than water. When a material is less dense than another liquid material, the material floats in the denser material. Cutting holes in the material will not reduce the buoyancy of the material. If the material had not floated as a single solid piece, then it will be said to be denser than the liquid material, and in such a case, if a strategic hole is cut on it to reduce its weight while maintaining its immediate volume, then it can be made to float. This is the principle behind metal floating ships.

Answer:

Option d = all of the above.

Explanation:

This question is more of a driving lesson or tutorial Question and not that scientific, it is logical and the "rule" attached to reversing and driving that is operating of vehicles especially cars, trucks and so on.

All the options given in the Question from option 'a' to option 'c' are all correct when driving backwards that is reversing or backing . Driving backward(backing or reversing) is not as easy as during forward (drive mode).

=> " Position your right hand on the back of the passenger seat. Grip the steering wheel at the 12 o’clock position with your left hand"

REASON: FOR BALANCING.

=> " Move the wheel left or right in the direction in which you want the rear of the vehicle to go."

The above, given in the Question are all correct.

When backing straight or to the right, all of the mentioned options are correct and recommended practices are to Position your right hand on the back of the passenger seat. The correct option is option d.

a) Position your right hand on the back of the passenger seat: This is a technique used by some drivers to help them have a better sense of the vehicle's position and reference point while backing up.

b) Grip the steering wheel at the 12 o'clock position with your left hand: This hand position allows for better control and maneuverability of the steering wheel while backing up.

c) Move the wheel left or right in the direction in which you want the rear of the vehicle to go: This is the fundamental principle of steering while backing up. By turning the wheel in the desired direction, you can guide the rear of the vehicle in that direction.

Therefore, These practices can assist in improving control, visibility, and maneuverability while backing up, ensuring a safer and more effective backing maneuver. The correct option is option d.

To know more about the principle of steering:

https://brainly.com/question/29458022

#SPJ6

Answer:

c) A series of RC circuits.

Answer:

Explanation:

Magnetic field = permeability x turn density x current

Magnetic field = 0.22T

turn density = 4150 /1.6 = 2593.75 t/m

permeability : µ = k µ°

µ°= 4 π 10^-7

k = 1

I = 0.22 / 4 π 10^-7 * 2593.75 = 0.22 10^7 /32594 = 67.497 A

Explanation:

A theory is a way of explaining an object or event using a set of facts.

Explanation:

Given:

distance between two sphere =0.35 m

Electrical repel force =0.035 N

Electrical repel force after connecting wire =0.055 N.

The electrical force between the two spheres:

[tex]F=k \frac{q_{1} q_{2}}{r^{2}}[/tex]

The electrical force between the two spheres after the wire is attached and removed:

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

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

[tex]q=r \sqrt{\frac{F}{k}}=0.35 \times \sqrt{\frac{0.055}{8.99 \times 10^{9}}}=6.46 \times 10^{-7} \mathrm{C}[/tex]

So the total charge of the two spheres [tex]=2 q=2 \times 6.46 \times 10^{-7}=1.29 \times 10^{-6} \mathrm{C}[/tex]

Then before connecting the wire, one sphere charge was [tex]q[tex] and the charge of the other sphere was [tex]\left(1.29 \times 10^{-6}-q\right)[/tex]

The electrical force between the two spheres before connecting the wire:

[tex]F=k \frac{q\left(1.29 \times 10^{-6}-q\right)}{r^{2}}[/tex]

[tex]q\left(1.29 \times 10^{-6}-q\right)=\frac{F r^{2}}{k}=\frac{0.035 \times(0.35)^{2}}{8.99 \times 10^{9}}=0.348 \times 10^{-12}[/tex]

[tex]-q^{2}+\left(1.29 \times 10^{-6}\right) q-\left(0.348 \times 10^{-12}\right)=0[/tex]

[tex]-q^{2}+\left(1.29 \times 10^{-6}\right) q-\left(0.348 \times 10^{-12}\right)=0[/tex]

Answer:

[tex]D.\ 970\ N[/tex]

Explanation:

Given:

Mass of Piano: 99kg

Required:

Calculate its weight

The weight of an object is calculate as thus;

[tex]Weight = Mass\ (m) * Acceleration\ due\ to\ gravity\ (g)[/tex]

[tex]m = 99kg[/tex] and [tex]g = 9.8m/s^2[/tex]

The formula becomes

[tex]Weight = 99kg * 9.8m/s^2[/tex]

[tex]Weight = 970.2\ kgm/s^2[/tex]

[tex]Weight = 970.2\ N[/tex]

[tex]Weight = 970\ N[/tex] Approximated

Hence, the weight of the piano is 970N

Answer:

a)4500V

b)750V

Explanation:

Given:

Distance between the plate=

6.00 cm

We need to convert to m

Then the Distance between the plate=

0.06m

electric field strength between two parallel plates =

7.50 × 104 V/m .

Then E= 7.50 × 104 V/m .

(a) What is the potential difference between the plates?

potential difference between the plates can be calculated using the formula below

Δ Vab=ED

Where E is the given electric field strength

D= The Distance between the plate

ΔVab=7.50 × 10⁴V/m ×

0.06m

= 4500V

(b) The plate with the lowest potential is taken to be zero volts. What is the potential 1.00 cm from that plate and 6.00 cm from the other?

the potential 1cm from the zero volt plate

Then the 1cm must be converted to m

= 0.01m

Let us say plate A as the plate at 0 volts:

The potential increases linearly going from plate A (0 V) to plate B (4500V).

Therefore,if the potential difference between A and B, separated by 6 cm, is 4500 V, then the potential difference between A and a point located at 1 cm from A is can be calculated also

If the plate with Lowest potential is taken to be zero then

=ΔVab=Vab-Vb=Va-0=Va=ED

Va=7.50 × 10⁴V/m × 0.01=750V

Answer: 43.2 J

Explanation:

Work = change in KE

initial KE = 0

final KE = 1/2mv^2 = 1/2(0.370 kg)(15.2778 m/s)^2 = 43.2 J

i'm not sure about sig figs though

Answer:

acceleration is the answer

Answer:

Acceleration

Explanation:

Answer:

Energy is released in this reaction possibly in the form of heat thus it is an exergonic and or exothermic reaction.

Explanation:

The energy is sometimes transferred as heat, inflicting the reaction mixture and its surroundings to become hotter. The temperature increase may be detected employing a measuring device. Some samples of exothermic reactions are: Combustion .An chemical reaction may be a chemical process that releases energy by lightweight or heat

Hope this helps...

Have a nice day!!!!

Answer:

The time it will take for the object to hit the ground will be 4.

Explanation:

You have:

h(t)=−16t²+v0*t+h0

Being v0 the initial velocity (54 ft/s) and  h0 the initial height (40 ft) and replacing you get:

h(t)=−16t²+54*t+40

To know how long it will take for the object to touch the ground, the height h(t) must be zero. So:

0=−16t²+54*t+40

Being a quadratic function or parabola: f (x) = a*x² + b*x + c, the roots or zeros of the quadratic function are those values ​​of x for which the expression is 0. Graphically, the roots correspond to the points where the parabola intersects the x axis. To calculate the roots the expression is used:

[tex]\frac{-b+-\sqrt{b^{2}-4*a*c } }{2*a}[/tex]

In this case you have that:

Replacing in the expression of the calculation of roots you get:

[tex]\frac{-54+\sqrt{54^{2}-4*(-16)*40 } }{2*(-16)}[/tex]  Expresion (A)

and

[tex]\frac{-54-\sqrt{54^{2}-4*(-16)*40 } }{2*(-16)}[/tex] Expresion (B)

Solving the Expresion (A):

[tex]\frac{-54+\sqrt{5476 } }{2*(-16)}= \frac{-54+74}{2*(-16)}=\frac{20}{2*(-16)}=\frac{20}{-32}= -\frac{5}{8}[/tex]

Solving the Expresion (B):

[tex]\frac{-54-\sqrt{5476 } }{2*(-16)}= \frac{-54-74}{2*(-16)}=\frac{-128}{2*(-16)}=\frac{-128}{-32}= 4[/tex]

These results indicate the time it will take for the object to hit the ground can be -5/8 and 4. Since the time cannot be negative, then the time it will take for the object to hit the ground will be 4.

Answer:

4 seconds

Explanation:

i checked on the test and the other person was right give them brainliest

Answer:

A car driving in a straight line 20 m/s

Explanation:

ayepecks silly

Answer:

Explanation:

1. A parsec is defined as the distance from the Sun which would result in a parallax of_TWO____ arcsecond as seen from Earth when observed 6 months apart.

2. One parsecs is about_3.3____light years

3. The more distant a star, the_LESS ____its parallax.

4. The statement "we can measure stellar parallax for most stars in our galaxy" is__TRUE .___.

5. The closest stars have parallaxes smaller than_.002 _____arcsecond.

6. The first successful measurements of stellar parallax were made by_Friedrich Bessel_____in year_1838_____for the star named.

7. Star Fred has parallax four times greater than star Bob. Star Fred is__4____times_nearer_____than star Bob.

Explanation:

Given,

I = 5 A

V = 240 V

T = 25 mins = 1500 sec

Now,

Energy dissipated = IVT= 5×240×1500 = 1800000 J

Answer:

V = 268.8 m/s

Explanation:

The speed of a wave in general is given by the following formula:

V = fλ

where,

V = Speed of that wave

f = Frequency of the wave

λ = wavelength of the wave

In this case we have a sound wave, travelling across carbon dioxide. The properties of sound wave are as follows:

V = Speed of Sound in Carbon dioxide = ?

f = frequency of sound wave = 140 Hz

λ = wavelength of sound wave = 1.92 m

Therefore,

V = (140 Hz)(1.92 m)

V = 268.8 m/s

Answer: hello i am a hacker

Explanation:

magnesium sulphate=(24*1)+(32*1)+(16*4)=120                                                             water=H2O=(1*2)+(1*16)=18                                                                                                        carbon dioxide=CO2=(12*1)+(16*2)=44                                                                                     ammonia=NH3=(14*1)+(1*3)=17                                                                                                   alminiumsulphate=AL2(SO4)3=(26*2)+(32*3)+(12*16)=340                                                          hydrogen peroxide=H2O2=(1*2)+(16*2)=34                                                              zinc sulphate=ZNSO4=(65*1)+(32*1)+(16*4)=161

Answer:

Work input W = -200.39 KJ

Explanation:

From the question, we are given;

m = 1.15 kg

Constant temperature T1 = T2 = 27 + 273 = 300k

Since the temperature is constant, we can say that the process is isothermal

P1 = 111 KPa

P2 = 0.84 MPa = 0.84 * 1000 KPa = 840 KPa

Now what we want to calculate is W1-2

Mathematically, for isothermal process;

W1-2 = mRTlnP1/P2

where R can be obtained from table and it is equal to 0.287 KJ/kg.k

Hence;

W1-2 = (1.15)(0.287)(300)(ln 111/840)

W1-2 = 99.015 * -2.023871690525 = -200.39 KJ

Kindly note that the value of the work is negative because work is done on the system and not by the system

Answer:

1.2 kg m²

Explanation:

Angular momentum is conserved:

L = L

Iω = Iω

(4.6 kg m²) (1.0 rev / 1.5 s) = I (2.5 rev/s)

I = 1.2 kg m²

Answer:

Explanation:

Let the angle required be θ with direction opposite to current .

cos θ = 3 / 5

θ = 53° .

Resultant velocity towards the opposite side

= √ ( 5 ² - 3²)

= 4 km /h

distance covered = 1.2 km

time taken = 1.2 / 4 = .3 h

= 18 min .

Answer:

i. Distance covered is 12 kilometres.

ii. Her displacement is 8.6 kilometres.

Explanation:

Distance is a span of length between two points, while displacement is the distance moved in a specified direction. Distance is a scalar quantity, while displacement is a vector.

She drives 7 kilometres north, then 5 kilometres east later.

i. Distance covered = 5 + 7

                                 = 12

Her distance covered is 12 kilometres.

ii. To determine her displacement, apply the Pythagoras rule to the sketch of her journey.

[tex]x^{2}[/tex] = [tex]5^{2}[/tex] + [tex]7^{2}[/tex]

   = 25 + 49

   = 74

x = [tex]\sqrt{74}[/tex]

  = 8.6023

Thus, her displacement is 8.6 kilometres.

Answer:

Work done by charge (W) = 0.050 (Approx)

Explanation:

Given:

Charge (q) = 0.0042 C

Potential difference(V) = 12.0 V

Find:

Work done by charge

Computation:

Work done(W) = qV

Work done by charge (W) = (0.0042)(12)

Work done by charge (W) = 0.0504

Work done by charge (W) = 0.050 (Approx)

Answer:

Work done by charge (W) = 0.050 (Approx)

Explanation:

Charge (q) = 0.0042 C

Potential difference(V) = 12.0 V

Find:

Work done by charge

Computation:

Work done(W) = qV

Work done by charge (W) = (0.0042)(12)

Work done by charge (W) = 0.0504

Work done by charge (W) = 0.050 (Approx)

Answer:

False

Explanation:

Total internal reflection is a condition that occurs when light travels from dense medium to less dense medium.

From the table given in the question above,

Refractive Index of Whale oil = 1.460

Refractive Index of vacuum = 1

From the above, we can see that the whale oil has a higher Refractive Index than vacuum. This implies that the whale oil is denser than the vacuum.

Therefore, total internal reflection will occur when light travels from whale oil to vacuum because the whale oil is denser than the vacuum.

Answer: A. The forces on an object in motion are balanced.

Explanation:

The dynamic equilibrium is defined as the phase when an object moves at a constant velocity such that all forces on the object are balanced.

Simple case of dynamic equilibrium: A horizontal force is applied to an object making it run with a constant velocity across a surface.

Hence, the statement describes dynamic equilibrium is " The forces on an object in motion are balanced. "

So, the correct option is "A".

Answer:

Hope this helps!