Answer:
a horizontal force of 120N to Push the block into the floor is called net force
Based on your average reaction time, how much time would it take to react to a traffic situation and stop a car traveling at 60 mph (1 mph equals 0.45 m/s) if you could decelerate the car at a rate of -3.4m/s2?
What distance would you travel (in meters) as the car came to a stop in the above situation?
Avg Reaction time: 0.218 ms
Answer:
d = 106.41 m
Explanation:
Given that,
Initial speed of the car, u = 60 mph = 26.9 m/s
The deceleration in the car, a = -3.4 m/s²
The average reaction time, t = 0.218 m/s
It finally stops, final velocity, v = 0
We need to find the distance covered by the car as it come to a stop.
Using third equation of motion to find.
[tex]v^2-u^2=2ad\\\\d=\dfrac{v^2-u^2}{2a}\\\\d=\dfrac{0^2-26.9^2}{2\times (-3.4)}\\\\d=106.41 m[/tex]
So, the car will cover 106.41 m as it comes to a stop.
Henrietta is going off to her physics class, jogging down the sidewalk at a speed of 4.15 m/sm/s. Her husband Bruce suddenly realizes that she left in such a hurry that she forgot her lunch of bagels, so he runs to the window of their apartment, which is a height 55.2 mm above the street level and directly above the sidewalk, to throw them to her. Bruce throws them horizontally at a time 5.50 ss after Henrietta has passed below the window, and she catches them on the run. You can ignore air resistance.
(a) With what initial speed must Bruce throw the bagels so that Henrietta can catch the bag just before it hits the ground?
(b) Where is Henrietta when she catches the bagels?
Answer:
Explanation:
Distance travelled by Henrietta in 5.5 s = 4.15 x 5.5 = 22.825 m .
Time taken by lunch of bagels to fall vertically by 55.2 m . Let it be t .
s = ut + 1/2 g t²
55.2 = 0 + .5 x 9.8 x t²
t² = 11.26
t = 3.356 s
By the time the lunch of bagels touches the hand of Henrietta , she would have travelled further by distance
s = 3.356 x 4.15 = 13.9 m
She is now at distance of 22.825 + 13.9 = 36.725 m from window .
So lunch of bagels must travel a horizontal distance of 36.725 m in 3.356 s which the time of fall of bagel .
Speed of bagel = distance / time
= 36.725 / 3.356
= 10.94 m /s
b )
Henrietta is 36.725 m from window at the time when she catches the bangel.
When the material in the mantle cools off near the surface then sinks
down towards the core and get heated again and rises back towards the
surface it is called?
Condensation
О
The water cycle
O
Convection currents
О
Apples and Bananas.
PLEASE HELP THIS IS URGENT ITS FOR A TEST
Answer:
convection currents
Explanation:
what is the mathematical definition of momentum? what is a more conceptual or descriptive definition of momentum?
Answer:
Momentum can be defined as "mass in motion." All objects have mass; so if an object is moving, then it has momentum - it has its mass in motion.
Explanation:
An enclosure has an inside area of 50 m2, and its inside surface is black and is maintained at a constant temperature. A small opening in the enclosure has an area of 0.01 m2. The radiant power emitted from this opening is 48 W. What is the temperature of the interior enclosure wall, in K
Answer:
Explanation:
The enclosure will behave as black body . For black body , the formula for radiant energy is given by Stefan's law as follows
E = σ A T⁴ where σ = 5.67 x 10⁻⁸ W m⁻² T⁻⁴
Area A = .01 m²
E = 48 W
48 = .01 x 5.67 x 10⁻⁸ T⁴
T⁴ = 846.56 x 10⁸
T= 539 K
Following are the calculation to the temperature of the interior enclosure wall:
Given:
[tex]\to A_s=50\ m^2\\\\\to A_0=0.01\ m^2\\\\\to q_{rad}=48\ w\\\\\to \sigma = 5.67 \times 10^{-8}\ \frac{W}{m^{-2} T^{-4}} \\\\[/tex]
To find:
[tex]T_s=?[/tex]
Solution:
Using the value to calculate the surface is black radiates power:
[tex]\to q_{rad}=A_0 E_0 T_s\\\\\to q_{rad}=A_0 \sigma T_{s}^4\\\\\to 48=0.01 \times 5.67 \times 10^{-8} \times T_{s}^4\\\\[/tex]
[tex]\to T_{s}^4 =\frac{48}{0.01 \times 5.67 \times 10^{-8}} \\\\[/tex]
[tex]=\frac{48\times 100}{ 5.67 \times 10^{-8}} \\\\=\frac{48\times 100\times 10^{8} }{ 5.67 } \\\\=\frac{48\times 10^{10} }{ 5.67 } \\\\=8.46\times 10^{10} \\\\[/tex]
[tex]\to \bold{T_s=\pm 539.31 \ K}[/tex]
Therefore the final answer is "[tex]\bold{\pm 539.31 \ K}[/tex]".
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PLS HELP In which situation is work being done? (Check all that apply.) Your answer:
A boy coasting down the sidewalk on a skateboard.
Lifting your binder out of your backpack into your top row locker.
Pushing a shopping cart down the aisle at Publix.
Pushing on a broken down car but it doesn’t move.
The legs on your science table holding up the table top.
Carrying a heavy backpack down the hall.
Answer:
Lifting your binder out of your backpack into your top row locker.
Pushing a shopping cart down the aisle at Publix
Explanation:
These are the only two in which an object is moving because of an applied force
.1 An 8-ft 3 tank contains air at an initial temperature of 808F and initial pressure of 100 lbf/in. 2 The tank develops a small hole, and air leaks from the tank at a constant rate of 0.03 lb/s for 90 s until the pressure of the air remaining in the tank is 30 lbf/in. 2 Employing the ideal gas model, determine the final temperature, in 8F, of the air remaining in the tank
Correct temperature is 80°F
Answer:
T_f = 38.83°F
Explanation:
We are given;
Volume; V = 8 ft³
Initial Pressure; P_i = 100 lbf/in² = 100 × 12² lbf/ft²
Initial temperature; T_i = 80°F = 539.67 °R
Time for outlet flow; t_o = 90 s
Mass flow rate at outlet; m'_o = 0.03 lb/s
Final pressure; P_f = 30 lbf/in² = 30 × 12² lbf/ft²
Now, from ideal gas equation,
Pv = RT
Where v is initial specific volume
R is ideal gas constant = 53.33 ft.lbf/°R
Thus;
v = RT/P
v_i = 53.33 × 539.67/(100 × 12²)
v_i = 2 ft³/lb
Formula for initial mass is;
m_i = V/v_i
m_i = 8/2
m_i = 4 lb
Now change in mass is given as;
Δm = m'_o × t_o
Δm = 0.03 × 90
Δm = 2.7 lb
Now,
m_f = m_i - Δm
Thus; m_f = 4 - 2.7
m_f = 1.3 lb
Similarly in above;
v_f = V/m_f
v_f = 8/1.3
v_f = 6.154 ft³/lb
Again;
Pv = RT
Thus;
T_f = P_f•v_f/R
T_f = (30 × 12² × 6.154)/53.33
T_f = 498.5°R
Converting to °F gives;
T_f = 38.83°F
The final temperature, in °F, of the air remaining in the tank is 38.83°F
It is given that volume V = 8 ft³
Initial Pressure Pi = 100 lbf/in² = 100 × 12² lbf/ft²
Initial temperature Ti = 80°F = 539.67 °R
Time for outlet flow; to = 90 s
Mass flow rate at outlet; m'o = 0.03 lb/s
Final pressure; Pf = 30 lbf/in² = 30 × 12² lbf/ft²
Now, from ideal gas equation,
Pv = RT
where v is initial volume, R is ideal gas constant = 53.33 ft.lbf/°R
[tex]v = RT/P\\ \\ v_i = 53.33 *539.67/(100*12^2)\\ \\ v_i = 2 ft^3/lb [/tex]
The initial mass is;
[tex]m_i = V/v_i\\ \\ m_i = 8/2\\ \\ m_i = 4 lb [/tex]
Now change in mass is given as;
Δm = [tex]m'_o*t_o[/tex]
Δm = 0.03 × 90
Δm = 2.7 lb
[tex]m_f[/tex] = [tex]m_i[/tex] - Δm
[tex]m_f[/tex] = 4 - 2.7
[tex]m_f[/tex] = 1.3 lb
now,
[tex]v_f = V/m_f\\ \\ v_f = 8/1.3\\ \\ v_f = 6.154 f^3/lb [/tex]
From the gas equation
Pv = RT
Final state:
[tex]T_f = P_fv_f/R\\\\ T_f = (30*12^2*6.154)/53.33\\\\ T_f = 498.5^oR [/tex]
Converting to °F:
[tex]T_f[/tex] = 38.83°F is the final temperature.
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help? its a short question
Answer:
i think its ancestor
Explanation:
sry if im wrong
Answer:
scientists compare organisms DNA to support the theory that all species share a common Ancestor.
A single, monochromatic indigo light source is shined through an etched, flat prism with a slit separation of .0250mm. The resulting interference pattern is viewed on a screen 1.25m away. The third maximum is found to be 6.6cm from the central maximum. What is the wavelength of the indigo light
Answer:
λ = 440 nm
Explanation:
The phenomenon of constructive interference is described by the expressions
d sin θ= m λ (1)
where d is the separation of the slits d = 0.0250 mm = 2.50 10⁻⁵ m, lam is the wavelength of the incident radiation and m is an integer indicating the order of interference
let's use trigonometry to find the angle
tan θ = y / L
where L is the distance to the screen L = 1.25 m
in general interference experiments angles are very small
tan θ = [tex]\frac{sin \ \theta }{cos \ \theta}[/tex]
ten θ = sin θ
substituting
sin θ = y / L
we substitute 1
d y / L = m λ
λ = [tex]\frac{ d \ y }{m \ L}[/tex]
in the exercise indicate
m = 3
y = 6.6 cm = 6.6 10-2 m
we calculate
λ = 2.50 10⁻⁵ 6.6 10⁻² /( 3 1.25)
λ = 4.4 10⁻⁷ m
let's reduce to nm
λ = 4.4 10⁻⁷ m (10⁹ nm / 1 m)
λ = 440 nm
A 6.00 nC is 2.00 m from a 3.00 nC charge. Find the magnitude of the electric field at a point midway between
the two charges? Which way does the electric field point, towards the positive or the negative charge?
Answer:
E_total = 26.97 N/C
Electric field points towards the positive charge
Explanation:
We are given;
Charge 1; q1 = 6 nC = 6 × 10^(-9) C
Charge 2; q2 = 3 nC = 3 × 10^(-9) C
Distance between both charges; R_o = 2 m
Since we want to find electric field midway, the distance midway is r = 2/2 = 1 m
Using coulumbs law;
E = kq/r²
Where k is a constant with a value of 8.99 × 10^(9) N.m/C²
Thus;
E1 = kq1/r²
E1 = (8.99 × 10^(9) × 6 × 10^(-9))/1²
E1 = 53.94 N/C
Similarly;
E2 = kq2/r²
E2 = (8.99 × 10^(9) × 3 × 10^(-9))/1²
E2 = 26.97 N/C
Since both electric fields are positive, it means that they are both moving towards the midpoint of the distance between both charges.
This implies they will have opposite directions.
Thus, total electric field at the midway point is;
E_total = E1 - E2
E_total = 53.94 - 26.97
E_total = 26.97 N/C
Describe the political actions that led to successful conservation in both stories.
Answer:
The political actions that led to successful conservation in both stories were what they call an FC company that makes the forest industry true. They make it out of a factory and it can make it very successful and accomplished.
Explanation:
You are inside the Great Hall, 15 m from the north wall with the doors to the RMC, and centered between two open doors that are 3 m apart. Someone is blairing a 200 Hz tone outside the Great Hall so that it enters the doors as a plane wave. You hear a maximum intensity in your current position. As you walk along the direction of the wall with the doors (but maintain a distance 15 m from the wall), how far will you walk (in m) to hear a minimum in the sound intensity
Answer:
Δr = 0.425 m
Explanation:
This is a sound interference exercise, the expression for destructive interference is
Δr = (2n + 1) λ / 2
in this case the movement is in the same direction as the sound, therefore the movement is one-dimensional
let's use the relationship between the speed of sound and its frequency and wavelength
v = λ f
λ = v / f
the first minium occurs for n = 0
Δr = λ / 2
Δr = v / 2f
Δr = [tex]\frac{340}{2 \ 400}[/tex]
Δr = 0.425 m
this is the distance from the current position that we assume in the center of the room
Arturo and Bianca are discussing the speeds of cars A and B. Arturo says: It looks like when the time is exactly 1.0s, the speed of Car B is greater than the speed of Car A. Bianca says: It also looks to me like the speed of Cars A and B are exactly the same at about 2.0s. Do you agree or disagree with Arturo and Bianca
Answer:
he two people agree with your answer
v_B = v_{oB} - a t
v_A = cte
Explanation:
To analyze if they are both in Kurdish, let's see the movement of the two cars
at t = 1s
the velocity of carriage B is greater than the speed of carriage a
v_B> v_A
at t = 2 s
the speed of the two cars is nipple
v_B = v_A
For this to be true, the speed of car B must be decreasing
v_B = v_{oB} - a t
v_A = cte
therefore the two people agree with your answer
A wheelbarrow is pushed 10 meters with a force of 75 N for 30 seconds. What is the work done?
How much power is needed?
Starting from the front door of your ranch house, you walk 55.0 mm due east to your windmill, turn around, and then slowly walk 40.0 mm west to a bench, where you sit and watch the sunrise. It takes you 25.0 ss to walk from your house to the windmill and then 37.0 ss to walk from the windmill to the bench.
Required:
a. For the entire trip from your front door to the bench, what is your average velocity?
b. For the entire trip from your front door to the bench, what is your average speed?
Answer:
a) V = 0.24 m/s
b) v = 1.53 m/s
Explanation:
In this case, we are asked to find two values that are pretty similar and use the same units, however, there are differences between them.
The average velocity is often referred to a vector quantity, therefore, if time is a scalar magnitude, we need to find the vector quantity of distance. In this case, is the displacement, which is also referred as a vector.
So, to calculate the average velocity we need to determine first the displacement of the person. As the person heads east and then west, his total displacement (D) is:
D = 55 - 40 = 15 m
Now the total time would be the time taken to go to the windmill and then, to a bench:
t = 25 + 37 = 62 s
Finally, the average speed is:
V = D/t
V = 15 / 62
V = 0.24 m/sThe average speed is a scalar magnitude, so we use the covered distance by the person (d) and the total time:
d = 40 + 55 = 95 m
Then, the speed:
v = 95/62
v = 1.53 m/sHope this helps
Which of the following is NOT a characteristic of noble gases?
unreactive
odorless
solid at room temperature
colorless
A car initially traveling at 15 m/s speeds up at a constant rate of 2.0 m/s2 for 3 seconds. The velocity of the car at the end of the 3 second interval is _________ m/s.
Answer:
Vf = 21 m/s
Explanation:
Data:
Initial Velocity (Vo) = 15 m/sAcceleration (a) = 2.0 m/s²Time (t) = 3 sFinal Velocity (Vf) = ?Use formula:
Vf = Vo + a * tReplace:
Vf = 15 m/s + 2.0 m/s² * 3sMultiply the acceleration with time:
Vf = 15 m/s + 6 m/sSolve the sum:
Vf = 21 m/sThe velocity of the car at the end of the 3 second interval is 21 meters per second.
Electric and gravitational forces have many similar features because they follow idenitical mathematical formulas. In particular,________ in electricity plays the equivalent role of mass in gravity, while_______ , plays a role corresponding to free-fall acceleration. Because of this kinematics describing projectiles in gravity would carry over to electricity, but the main difference is that in electricity we have__________ , while in gravity mass is always positive, which means gravity is_______ , but electricity________ .
Answer:
Electric and gravitational forces have many similar features because they follow idenitical mathematical formulas. In particular, Charge in electricity plays the equivalent role of mass in gravity, while electric field, plays a role corresponding to free-fall acceleration. Because of this kinematics describing projectiles in gravity would carry over to electricity, but the main difference is that in electricity we have positive and negative charges, while in gravity mass is always positive, which means gravity is always attractive, but electricity could be attractive and repulsive.
Explanation:
The formulas of Electric and gravitational fields are as follow
Electric Field
F(electric)=kq1q2/r^2
Gravitationlal Fieeld
F(grav)=GMm/r^2
As you see both follow the inverse square law in the formula
Both of these act between two bodies without having any contact. The gravitational field acts on the mass of an object Whereas the electric field acts on the charge.
The gravitational field can only attractive while the electric field can be attractive or repulsive.
Normally electric field is stronger than the gravitational field.
In particular, Charge in electricity plays the equivalent role of mass in gravity, while electric field,
What is gravitational force?Newton's law of gravity states that each particle having mass in the universe attracts each other particle with a force known as the gravitational force.
Gravitational force is proportional to the product of the masses of the two bodies and inversely proportional to the square of their distance.
Electric and gravitational forces have many similar features because they follow identical mathematical formulas.
In particular, Charge in electricity plays the equivalent role of mass in gravity, while electric field,
Plays a role corresponding to free-fall acceleration. Because of these kinematics describing projectiles in gravity would carry over to electricity,
but the main difference is that in electricity we have positive and negative charges, while in gravity mass is always positive,
which means gravity is always attractive, but electricity could be attractive and repulsive.
Hence, in particular, Charge in electricity plays the equivalent role of mass in gravity, while electric field,
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What is the mass of a block concrete that gains 52,800 joules of energy when its temperature is increased by 5 degrees Celsius specific heat of concrete 880 J/K degrees Celsius
Answer:
12 kg
Explanation:
q = 52,800 J
c = 880 J/(kg * K) Pretty sure you missed the kg here
ΔT = 5 °C = 5 K (reminder that this only applies to ΔT and not T)
q = mcΔT ⇒ m = q/(cΔT) = 52,800 J / (880 J/(kg * K) * 5 K) = 12 kg
The mass of a block concrete that gains 52,800 joules of energy when its temperature is increased by 5 degrees Celsius specific heat of concrete 880 J/K degrees Celsius is 12kg
The formula for calculating the quantity of heat energy absorbed by the block is expressed as:
Q = mcΔt
Q is the quantity of heat = 52,800 Joules
m is the mass of the concrete
c is the specific heat of concrete = 880 J/K
Δt is the change in temperature = 5 degrees
substitute the given values into the formula:
[tex]52800=m(880)(5)\\52800 = 4400m\\m=\frac{52800}{4400}\\m= 12kg[/tex]
Hence the mass of a block of concrete that gains 52,800 joules of energy when its temperature is increased by 5 degrees Celsius specific heat of concrete 880 J/K degrees Celsius is 12kg
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A helicopter is hovering at a constant height of 35 m. The upward lift force on the helicopter is 85500. What is the weight of the helicopter
Which of the following sentences is an example concerns smerne might have at lunchtime?
I would be to have brocoll stead of fres,
I wonder if my chicken is ooked all the way
I have never ordered smething I did not ke,
of ordered a salad with the dressing on the site
Answer:
yes
Explanation:
becausw yesnssjsdkwww
Can someone please help, ty!!
Will mark brainliest.
Answer:
#1 ( Balanced ) ( Rest)
#2 ( Unbalanced) ( Accelerating)
Explanation:
Suppose you had 10 identical molecules enclosed by a box. At a given instant, one molecule has an energy of 100 Joules, and the others are all stationary. (A) What is the average kinetic energy of the 10 molecules
Answer:
the average kinetic energy of the 10 molecules is 10 J.
Explanation:
Given;
energy on one molecule in motion, E = 100 J
number of molecules, n = 10
(A) The average kinetic energy of the 10 molecules
since the remaining 9 molecules are at rest, their kinetic energy = 0
[tex]E_{Avg} = \frac{E_1 + E_9}{10} \\\\E_{Avg} = \frac{100J+ 0}{10} \\\\E_{Avg} = \frac{100J}{10} \\\\E_{Avg} = 10J[/tex]
Therefore, the average kinetic energy of the 10 molecules is 10 J.
a sensor light installed on the edge of a home can detect motion for a distance of 50 feet in front and with a range of motion of 200 degrees. what is the arc length of the area covered
Answer:
4363.3231 feets²
Explanation:
Given that :
Distance, r = 50 ft
θ = 200°
The arc length of area covered :
Arc length = θ/360° * πr²
Arc length = (200/360) * 50 ft ^2 * π
Arc length = 0.5555555 * 2500 * π
Arc length = 4363.3231 feets²
What is the symbol for carbonate ?
Desperado, a roller coaster built in Nevada, has a mass of 800 kg. It also has a vertical drop of 225 feet down the first hill. The roller coaster is designed so that the speed of the cars at the end of this drop is 80 mi/h. Assume the cars are at rest at the start of the drop. How much work is done by friction on the car as it drops down the hill
Answer:
the work done by friction on the car is 524,582 J.
Explanation:
Given;
mass of the roller coaster, m = 800 kg
distance moved by the coaster, d = 225 ft = 68.58 m
final velocity of the coaster, v = 80 mi/h = 35.76 m/s
The time taken for the coaster to drop down the hill is calculated as;
[tex]t = \sqrt{\frac{2h}{g} } \\\\t = \sqrt{\frac{2\ \times \ 68.58}{9.8} } \\\\t = 3.74 \ s[/tex]
The work done by friction on the car is calculated as;
[tex]W =F\ \times \ d = \frac{mv}{t} \times \ d\\\\W = \frac{800 \ \times \ 35.76 }{3.74} \times \ 68.58\\\\W = 524,582 \ J[/tex]
Therefore, the work done by friction on the car is 524,582 J.
Which of the following is a physical quantity that has a magnitude but not
direction?
- vector
- frame of reference
- scalar
- resultant
Answer:
Scalar
Explanation:
A scalar quantity is a physical quantity that has magnitude but no directional attribute.
An example of a scalar is speed and distance.
A vector is a physical quantity that has both magnitude and direction.
An example is displacement and velocity.
Scalar has only the magnitude value specified and nothing else.
A student stretches a spring, attaches a 1.20 kg mass to it, and releases the mass from rest on a frictionless surface. The resulting oscillation has a period of 0.750 s and an amplitude of 15.0 cm. Determine the oscillation frequency, the spring constant, and the speed of the mass when it is halfway to the equilibrium position.
Answer:
the speed of the mass when it is halfway to the equilibrium position is 1.26 m/s
Explanation:
Given that;
mass of the object m = 1.20 kg
period of oscillation = 0.750 s
Amplitude ( A/x) = 15.0 cm = 0.15 m
now;
a) Determine the oscillation frequency;
oscillation frequency f = 1/T
we substitute
f = 1 / 0.750 s
f = 1.33 Hz
Therefore, the oscillation frequency is 1.33 Hz
b) Determine the spring constant;
we solve for spring constant from the following expression;
T = 2π√(m/k)
k = 4π²m / T²
so we substitute
k = (4π² × 1.20) / (0.750)²
k = 47.3741 / 0.5625
k = 84.22 N/m
Therefore, the spring constant is 84.22 N/m
c) determine the speed of the mass when it is halfway to the equilibrium position
So, at equilibrium, the energy is equal to K.E
such that;
1/2mv² = 1/2kx²
mv² = kx²
v² = kx² / m
v = √( kx²/m)
we substitute
v = √( 84.22×(0.15 m)²/ 1.2 )
v = √( 1.89495 / 1.2 )
v = √ 1.579125
v = 1.26 m/s
Therefore, the speed of the mass when it is halfway to the equilibrium position is 1.26 m/s
A 200-N force acts on a 10-kg object. The acceleration of the object is
I have a massive rock weighing 3,000 Newtons but I can only accelerate it to 500 m/s2 what is its mass?
Answer:
6 kg
Explanation:
F=ma
F is Force(newtons)
m is mass(kg)
a is acceleration(m/s^2)
Plug in the numbers
3000 = m(500)
divide both sides by 500 to cancel out the 500.
3000/500=6
6 = m
6kg is the mass