Answer:
The velocity at impact is 222.2 m/s
Explanation:
The given information are;
The time at which the woman heard the sound of the coin after dropping it into the wishing well = 30 seconds
The average speed of sound in air = 344 m/s
The time in which the dime travel = t₁
The time in which the sound travel = t₂
1/2 × 9.8 × t₁² = 344 × t₂
t₁ + t₂ = 30
4.9·t₁² = 344 × (30 - t₁)
4.9·t₁² + 344·t₁ - 10320 = 0
Which gives -344±
[tex]t_1 = \dfrac{-344\pm \sqrt{344^{2}-4\times 4.9 \times 10320}}{2\times 4.9}[/tex]
t₁ = 22.676 seconds or -92.9 seconds
Therefore the correct natural time is t₁ = 22.676 seconds
The velocity at impact, v = g×t₁ = 9.8 × 22.676 = 222.2 m/s
The velocity at impact= 222.2 m/s.
a ball is thrown down at 25 m/s from a 500m tall building. how fast is it traveling when it hits the ground?
Answer:
The speed of the ball when it hits the ground is 102.1 m/s
Explanation:
Given;
initial velocity of ball, u = 25 m/s
distance traveled by the ball = height of the building = h = 500 m
when the ball hits the ground, the final velocity, v = ?
The final velocity of the ball is given by;
v² = u² + 2gh
where;
g is acceleration due to gravity = 9.8 m/s²
v² = (25)² + 2(9.8)(500)
v² = 10425
v = √10425
v = 102.1 m/s
Therefore, the speed of the ball when it hits the ground is 102.1 m/s
a ballon filled with nitrogen gas has a small leak. Another ballon filled with hydrogen gas has an identical leak. How much faster will the hydrogen balloon deflate
Answer:
4 times that of nitrogen gas, N2.
Explanation:
Let R1 be the rate of diffusion of nitrogen gas, N2.
Let R2 be the rate of diffusion of Hydrogen gas, H2.
Let M1 be the molar mass N2
Let M2 be the molar mass of H2.
Next, we shall determine the molar mass of N2 and H2.
This is illustrated below below:
Molar mass of N2 (M1) = 2 x 14 = 28 g/mol
Molar mass of H2 (M2) = 2 x 1 = 2 g/mol
Finally, we shall determine the rate of diffusion of Hydrogen gas, H2 as follow:
R1/R2 = √(M2/M1)
M1 = 28
M2 = 2
R1/R2 = √(M2/M1)
R1/R2 = √(2/28)
R1/R2 = √(1/14)
R1/R2 = 0.27
Cross multiply
R1 = R2 × 0.27
Divide both side by 0.27
R2 = R1/0.27
R2 = R1 × 1/0.27
R2 = R1 × 4
R2 = 4R1
Therefore, the rate of diffusion of H2 (R2) is 4 times that of N2 (R1)
A running back with a mass of 70 kg travels down the field with a velocity of 5.0 ms . Calculate the kinetic energy of the football player
Explanation:
KE = ½ mv²
KE = ½ (70 kg) (5.0 m/s)²
KE = 875 J
A submarine completed a 450 km training with an average speed of 50 km/h. For the first 180 km, it travelled at an average speed of 60 km/h. What was the average speed for the remaining distance? Km/h
Answer:
45km/hr
Explanation:
Total distance=450km
Total speed=50km/hr
Total time= distance/speed
=450/50
=9hrs
distance a=180km
speed a=60km/hr
Time a=180/60
=3hrs
Distance b=450-180=270km
Speed b=?
Time b=270/speed b
Total time=time a + time b
9=3+(270/speed b)
270/speed b =9-3
270/speed b =6
6*speed b =270
Speed b=270/6
Speed b=45km/hr
Answer:
45km/hr
Explanation:
Total distance=450km
Total speed=50km/hr
Total time= distance/speed
=450/50
=9hrs
distance a=180km
speed a=60km/hr
Time a=180/60
=3hrs
Distance b=450-180=270km
Speed b=?
Time b=270/speed b
Total time=time a + time b
9=3+(270/speed b)
270/speed b =9-3
270/speed b =6
6*speed b =270
Speed b=270/6
Speed b=45km/hr
Perform the calculation and report your answer using sig figs. 126.3851 + 7.2 + 73.607 + 15.98
Answer:
223.2
Explanation:
126.3851 + 7.2 + 73.607 + 15.98 = 223.1721
When adding/subtracting, round to the fewest decimal places. 7.2 has 1 number after the decimal point, so we'll round our answer to 223.2.
A ball rolling on the floor is an example of motion. a random b) translatory c) multiple d) rotatory
Answer:
Actually it is linear motion but here option is not given so the best option is translators motion.
Explanation:
Hope it will help you :)
Answer:
d rotatory motion
Explanation:
who was albert einstien describe his contributions???
Answer:
Albert Einstein was from Germany he was born theoritical physicist, from childhood only he loved mechanical toys, he was highly gifted in Mathematics, He was a world citizen and a scientific genius too. His contribution were:
1) he developed the theory of relativity
2) he also discovered the process of nuclear fission
3)he developed the quantum theory of specific heat
4)theory of stimulated emission, on which laser device technology is based
5) law of photoelectric effect
hope it helped you :)
Question 2 (1 point)
In a competition, an athlete threw a flying disk 178.7 meters through the air. While
in flight, the disk traveled at an average speed of 13.6 m/s. How long did the disk
remain in the air?
Your Answer:
Answer
units
How does work affect energy between objects so it can cause a change in the form of energy? Work transfers energy. Work changes energy. Work increases energy. Work decreases energy.
'Doing work' is a way of transferring energy from one object to another, energy is transferred when a force moves through a distance.
If i explain with formula
Work done (J) = Energy transferred (J)
So more energy, more work done bc u transferred more energy to move the object and doing the work. and if you only use a little of energy, the work done also only a little.
Work affect energy between objects so it can cause a change in the form of energy by transferring energy.
According to work energy theorem, the work done on an object is directly proportional to the change in the average kinetic energy of the body.
For example, a catapult used to project a stone, does a work by converting or transferring its stored elastic potential energy into kinetic energy of the flying stone.Thus, we can conclude that work affect energy between objects so it can cause a change in the form of energy by transferring energy.
Learn more here: https://brainly.com/question/10063455
Q3. Three ants 1, 2 and 3 are pulling a grain with forces of magnitude 10 N, 4 N and FN as shown in the figure. Find the force F if the grain remains in equilibrium under the action of the above forces.
Answer:
F = 7.21 N
Explanation:
There are two methods to find the magnitude of F.
The first method is the analytical one and the second one is the geometrical one.
The easiest is the geometrical one.
We will start with it
■■■■■■■■■■■■■■■■■■■■■■■■■■
● Method 1:
The geometrical method
The grain remains in equilibrum under the action of 3 forces.
The 3 forces must give if joined together a close path.
There are 3 forces so the resulting shape is a triangle. (Picture 1)
● Al Kashi theorem:
We will use Al Kashi theorem (law of cosine) to find the magnitude of F.
● F^2 = b^2 + c^2 + 2bc×cosA
● F^2 = 10^2 + 4^2 + 2×10×4 × cos(37°)
● F^2 = 52.1
● F = 7.21 N
■■■■■■■■■■■■■■■■■■■■■■■■■■
● method 2 (analytical one)
This method is based on projecting each vector on the x and y axis.
Since the grain remains in equilibrum the relation between the vectors is:
● Vector F + Vector 1 + Vector 2 = Null vector
Vector one is the one with 4 N magnitude and 2 is the 10 one.
Project each vector following the x-axis and the y-axis and add them together.
(Picture 2)
● x-axis
F1 is the 4 N force and F2 is the 10 N one
● Fx + F1x + F2x = 0
● Fx -4 + 10 × cos(37°) = 0
F1x is negative since it goes toward the negatives numbers. It is parallel to the x-axis that's why we have put directly the magnitude
Fx2 is not parallel to the x-axis that's why we have expressed it using the cosine relation. (Picture 3)
● Fx -4 + 10 × cos(37°) = 0
● Fx = 4 -10 × cos(37°)
● Fx = -4 after rounding to the nearest unit
● y-axis
● Fy + F1y + F2y = 0
● Fy + 0 + sin(37°) × 10 = 0
F1y equals 0 since when projecting the vector's head and tail, both were in the same point. In other words the direction of the vector was perpendicular to the y-axis.
F2y is'nt parallel to the y-axis. That's why we have expressed it using the sine.
● Fy + sin(37°)×10 =0
● Fy = -10×sin(37°)
● Fy = -6 after rounding it to the nearers unit
Notice that F, Fx and Fy are creating a right triangle.(picture 4)
● The Pythagorian theorem
● F^2 = Fx^2 + Fy^2
● F^2 = (-4)^2 + (-6)^2
● F^2 = 16+36
● F^2 = 52
● F^2 = 7.21 N
That's the same result we got using the first method.
Answer:
F = 7.21 N
Explanation:
horizontal sum of forces = ∑h = 10 cos(37) - 4 = 3.98 N
vertical sum of forces = ∑v = 10 cos(90-37) = 6.02 N
therefore, the resultant F² = ∑h² + ∑v²
F = sqrt (3.98² + 6.02²)
F = 7.21 N
A pair of narrow, parallel slits separated by 0.275 mm is illuminated by the green component from a mercury vapor lamp (λ = 546.1 nm). The interference pattern is observed on a screen 1.25 m from the plane of the parallel slit. Calculate the distance from the central maximum to the first bright region on either side of the central maximum.
Answer:
2.481 mm
Explanation:
Given that
Distance between the slits, d = 0.275 mm = 2.75*10^-4 m
Wavelength of the lamp, λ = 546.1 nm
Distance between slit and the screen, L = 1.25 m
To solve this question, we would be applying the formula for Young's double slit fringes, from the path difference equal to a whole number of wavelengths.
mλ = dy/L
The question states that we should find the distance from the centre to the 1st order bright fringe, thus, m = 1
Now, we apply all these values into the question
1 * 546.1*10^-9 = (2.75*10^-4 * y) / 1.25
1.25 * 1 * 546.1*10^-9 = 2.75*10^-4 * y
6.825*10^-7 = 2.75*10^-4 * y
y = 6.825*10^-7 / 2.75*10^-4
y = 0.002481 m or 2.481 mm
From a hot air balloon that is at rest at a certain height, a projectile is launched horizontally at 30m / s, how fast will it have after 4s?
A. 50m / s
B. 60m / s
C. 70m / s
D. 80m / s
Answer:
A. 50 m/s
Explanation:
Given in the y direction:
v₀ = 0 m/s
a = 10 m/s²
t = 4 s
Find: v
v = at + v₀
v = (10 m/s²) (4 s) + 0 m/s
v = 40 m/s
In the x direction, the velocity is constant at 30 m/s.
The overall speed is:
v² = (30 m/s)² + (40 m/s)²
v = 50 m/s
The answer:
A) 50 m/s
A charge of 19 nC is uniformly distributed along a straight rod of length 15 m that is bent into a circular arc with a radius of 5.7 m. What is the magnitude of the electric field at the center of curvature of the arc?
Answer:
The magnitude of the electric field at the center of curvature of the arc is 3.87 N/C
Explanation:
Please see the attachments below
A tortoise travels 15 meters (m) west, then another 13 centimeters (cm) west. How many meters total has she walked?
Answer:
15.13m
Explanation:
change 15m to cm
1m=100cm
15m times 100=1500cm
add 1500+13 = 1513cm
in metres it will be 15.13m
Multiple of a unit of measure are found by multiplying the unit by an unteger larger than one
The total distance the tortoise walked in meters is 15.13 m
Reason:
Known parameter are;
The distance west the tortoise travels = 15 meters
The further distance west the tortoise walks = 13 cm = 0.13 m
Required:
The total (distance) in meters she has walked
Solution:
The total distance the tortoise walked in meters = 15 m + 0.13 m = 15.13 m
Learn more about multiples of units of measurement here:
https://brainly.com/question/1643372
andy runs 40 meters east in 5 seconds and then 100 meters west in 15 seconds his average velocity is?
Answer:
[tex]\Large \boxed{3}[/tex]
Explanation:
Info given;
∵ 40 meters east in 5 seconds
∵ 100 meters west in 15 seconds
=> [tex](100 -40)[/tex]
=> Divided by;
=> [tex](5 + 15)[/tex]
=> [tex]3 m/s[/tex]
Answer; 3 m/s
(Average velocity is; 3 m/s )
The work function for cesium is 1.96 eV. (a) Find the cutoff wavelength for the metal, (b) what is the maximum kinetic energy for the emitted electrons when 425 nm light is incident on the metal
Answer:
Explanation:
λ = hc/¢
Where
h = the Plank constant 6.63 x 10-34 Is
C = 3.0×10^8
¢= 1.96eV
= (6.63×10^-34Js)×(3×10^8)÷( 1.96eV) × 1eV/1.6×10^-19J
= (1.989×10^-25)÷( 1.96eV)×1eV/1.6×10^-19J
= 6.342×10^-7m
B) maximum kinetic energy
= K=hf−ϕ ........1
ϕ = hc
Where
h = constant 6.63 x 10^-34Js
ϕ= 1.96eV
Recall
λ =425×10^-9m
f = frequency in Hz
f = c / λ
C = 3.0×10^8
f = 3.0×10^8 / 425×10^-9m
f = 0.000705Hz
From equation 1
K = (6.63 x 10^-34Js×0.000705Hz )- 6.63 x 10^-34Js×3.0×10^8
= 4.68×10^-37 - 1.989×10^-25
= - 1.98×10^-25J
What is the magnitude of displacement if a person goes 290 m east followed by 150 m west?
Answer:140 m
Explanation:
Displacement = 290-150= 140 m
Ariver is flowing at 3.6 m/s. A boy in a tube is floating the river downstream. If the boy can use
his arms to paddle at 1.7 m/s with the current, how fast will it appear he is moving to anyone on
the riverbank?
Answer:
The total speed is 5.3 m/s
Explanation:
The speed of river = 3.6 m/s
The speed of the tube that a boy use for downstream = 1.7 m/s
Now we have to find the total speed of the boy in the case of downstream. However, in this case, the total speed can be determined by adding both the given speeds.
The total speed = Speed of rive + speed of the tube
Total speed = 3.6 + 1.7
Total speed = 5.3 m/s
Where on the periodic table would this element most likely be found? Group 1 Group 2 Group 12 Group 13
Answer:
The right approach will be Option C "Group 12".
Explanation:
A table that further arranges the chemical components in addition to expanding the electron configuration. Elements possessing identical characteristics are positioned in almost the same section (column or group), although elements in almost the same row become positioned with a similar amount of electron spheres.Group 12 components therefore partially replaced (n − 1)d subshells, and therefore aren't metals, technically accurate. However, although much their chemistry seems to be comparable to something like the components throughout the d block which includes establishing themselves.Some other options in question are not relevant to something like the given scenario. Because then the option here is just the right one.
Answer:
option C group 12
Explanation:
i did the test
How long will it take a charter bus full of people traveling 216 km/hr from Georgia to go 36 km to Florida's
Disney World theme park?
Answer:
t = 10.02 minutes
Explanation:
It is given that,
Speed of bus, v = 216 km/h
Distance to be traveled by the bus, d = 36 km
We need to find the time taken by the bus to cover the distance. Let the time is t.
Speed = distance/time
[tex]t=\dfrac{d}{v}\\\\t=\dfrac{36\ km}{216\ km/h}\\\\t=0.167\ h[/tex]
or
t = 10.02 minutes
So, 10.02 minutes is taken by the bus.
A cross country skier moves 28 meters westward then 62 meters eastward and finally 54 meters westward
Answer:
The answer is below
Explanation:
A cross-country skier moves 28 meters westward, then 62 meters eastward, and finally 54 meters westward.
For this motion, what is the distance moved?
What is the magnitude and direction of the displacement?
Answer:
a) The distance moved is the summation of all the distance, therefore:
Distance = Distance first moved westward + Distance moved eastward + Final distance moved westward = 28 m + 62 m + 54 m = 144 m
Distance = 144 m
b) Displacement is a vector quantity (has magnitude and direction). The displacement is the shortest distance from the starting to final point.
Total distance westward = 28 m + 54 m = 82 m
Total distance eastward = 62 m
Displacement = Total distance westward - Total distance eastward = 82 m - 62 m = 20 m
Displacement = 20 m westward
The displacement has a magnitude of 20 m and the direction is westward
No one can answer this, guaranteed
Answer:
T = 40.08 °C
Explanation:
Given:
m₁ = 0.33 kg, mass of iron horseshoe
T₁ = 693°C, initial temperature of horseshoe
c₁ = 448 J/(g-°C), specific heat
m₂ = 24 kg, mass of water
T₂ = 39°C, initial temperature of water
c₂ = 4186 J/(g-°C), specific heat of water
let T be the equilibrium temperature.
For energy balance,
m₁c₁(T₁ - T) = m₂c₂(T - T₂)
(0.330) * (448) * (693 - T) = (24) * (4186) * (T - 39)
147.84 * (693 - T) = 100,464 * (T - 39)
102,453.12 - 147.84T = 100,464T - 3,918,096
102,453.12 + 3,918,096 = 100,464T - 147.84T
4020549.12 = 100316.16T
T = 40.08 °C
Please help with theses 2 questions.
1. What is the name of 2F?
2.Using the diagram what is the name of the distance between O and 2F?
[tex] \huge{ \underline{ \underline{ \purple{ \bf{Answer:}}}}}[/tex]
1) Well, we know that lens is made by using 2 concave or convex mirror or sometimes we also use one plane mirror. The spherical mirrors are part of the glass sphere, and hence they have a centre and corresponding radius.
2F is double of focal length when light passes from one surface to another of the lens, so it can be said as the centre of curvature of the one of those spherical lens.
2) Distance between the optical centre and the centre of curvature is a lens can be termed as the radius of curvature of the lens. Well, we don't generally use these in case of lens. But still, the distance between O and 2F is double of the focal length or radius of curvature.
━━━━━━━━━━━━━━━━━━━━
Nail tips exert tremendous pressures when they are hit by hammers because they exert a large force over a small area. What force (in N) must be exerted on a nail with a circular tip of 1.45 mm diameter to create a pressure of 2.33 ✕ 109 N/m2? (This high pressure is possible because the hammer striking the nail is brought to rest in such a short distance.)
Answer:
The force is [tex]F = 3587.2 \ N[/tex]
Explanation:
From the question we are told that
The diameter is [tex]d = 1.4 \ mm = 0.0014 \ m[/tex]
The pressure is [tex]P = 2.33*10^{9} \ N/m^2[/tex]
Generally the radius is mathematically represented as
[tex]r = \frac{0.0014}{2}[/tex]
[tex]r = 0.0007 \ m[/tex]
The cross-sectional area of the nail is mathematically represented as
[tex]A = \pi r^2[/tex]
=> [tex]A = 3.142 * 0.0007 ^2[/tex]
=> [tex]A = 1.54 *10^{-6}[/tex]
Generally the pressure is mathematically represented as
[tex]P = \frac{F}{A}[/tex]
=> [tex]F = P * A[/tex]
=> [tex]F = 1.54*10^{-6} * 2.33*10^{9}[/tex]
=> [tex]F = 3587.2 \ N[/tex]
What does this student most likely need to do in order to be better prepared to stay safe in a lab?
take off the goggles
change into lighter shoes
wear different clothing
tie back her hair
she needs to tie back her hair
Suppose all of the apples have a mass of 0.10 kg. If apple (A) is sitting on the ground, what is its potential energy?
Answer:
The answer is C 0.0
Explanation:
Because its sitting still on the ground.
Answer:
0.0j
Explanation:
When two bodies of different temperatures are placed together and left for sometime, Both of them attain the same temperature.
(Heat flows from a body of Higher temperature to a body of lower temperature)
Now after they attain the same temperature will there be
No transfer of heat between them
Or
Will there be an equal amount of heat lost and gained by both the bodies?
My answer would be an equal amount of heat is lost and gained by both the bodies
You can't exactly say that there is no heat transfer just because equal amount is lost and gained by the bodies right?
My text book says that there is NO transfer of heat once both the bodies attain same temperature
hi olivia hope this helps you
Which acid is naturally found in foods and can be safe to eat? sulfuric acid citric acid hydrochloric acid nitric acid
Answer:
[tex]\Huge \boxed{\mathrm{citric \ acid}}[/tex]
Explanation:
Citric acid is naturally found in foods and can be safe to eat.
Citric acid is present in oranges, lemons, and other types of citrus fruits that we can eat.
The acid that is naturally found in foods and can be safe to eat would be citric acid, therefore the correct answer is option B .
What is a Chemical compound?
A chemical compound is a combination of two or more either similar or dissimilar chemical elements.
For example, H₂O is a chemical compound made up of two oxygen atoms and a single hydrogen atom.
As given in the problem statement we have to find out the acid from the given list of options that are naturally found in foods and can be safe to eat.
The sulphuric acid found in batteries, therefore, is not safe to eat, while the citric acid found in different fruits can be safe to eat.
The correct response is option B since citric acid is a naturally occurring acid that may be consumed without harm.
Learn more about a chemical compound here, refer to the link given below ;
brainly.com/question/12166462
#SPJ6
How does a arrow represent displacement
Answer:
An arrow represents displacement. Because it's a vector quantity.
Vector quantity= Direction+Magnitude
When an arrow is put above a unit like
accelerationdisplacementit means that it's a vector quantity.
Hope this helps ;) ❤❤❤
600 pages of a book have a total mass of 0.6kg; calculate the mass of each sheet of paper in the book in (i) Kilograms (ii) Milligram
Answer:
[tex]1g = 1000mg \\ \: \: \: \: \: \: \: \: = 0.001kg[/tex]
Explanation is attached to the picture
hope this helps
brainliest plz