Answer:
-0.55m/s
Explanation:
Given that: For the boy
Weight = 745N
Velocity = +0.35 m/s
Mass of the boy = ?
g = 9.81m/s^2
W = mg
745 = m×9.81
m = 75.94kg
For the girl
Given that:
Weight = 477 N
g = 9.81m/s^2
m = ?
W = mg
477 = m×9.81m/s^2
m = 48.62kg
To solve for the v of the girl, the two has to add up
48.62kg×v + 75.94kg×+0.35 m/s = 0
48.62v + 26.579 = 0
48.62v = - 26.579
v = -26.579/48.62
v = -0.5466
v = -0.55m/s
Hence, the velocity of the girl is -0.55m/s.
The negative sign is as a result of the two of them moving is opposite direction.
a projectile is shot upward from the surface of the earth with an initial velocity of 384 ft/s. What is its velocity after 5 seconds
Answer:
335 ft/s
Explanation:
In this question, we have a very important factor missing. The equation of the projectile. So, in simplifying the question I'm going to assume an equation which you can correct thereafter
s(t) = -4.9t² + v(0)t + s0
From the question, we're told that v(0) = 384 ft/s, so if we apply that, we have
s(t) = -4.9t² + 384t + s0, where s0 = 0
On differentiating the equation, we have
s(t) = v(t) = -4.9(2t) + 384(1)
v(t) = -9.8t + 384
Now, at time t = 5 seconds, the velocity v =
v(t) = -9.8(5) + 384
v(t) = -49 + 384
v(t) = 335 ft/s
Therefore, the velocity of the projectile after 5 seconds is 335 ft/s. Please leave a like if it helped you.
Compute the density in g/cm? of a piece of metal that has a mass of 0.450 kg and a volume of 52 cm3
Answer:
Ro = 8.65 [g/cm³]
Explanation:
We must remember that density is defined as the ratio of mass to volume.
[tex]Ro=m/V[/tex]
where:
m = mass = 0.450 [kg] = 450 [g]
V = volumen = 52 [cm³]
Ro = density [g/cm³]
Now replacing:
[tex]Ro = 450/52\\Ro = 8.65 [g/cm^{3} ][/tex]
two cars with initial speed 2v and v, lock their brakes and skid to a stop. what is the ratio of the distance travelled
Answer:
4:1
Explanation:
Given that the initial speed of the first car, u = 2v while the initial speed of the second car, u = v. To find the distance travelled, we are going to apply one of the equations of motion. The equation chosen is
v² = u² - 2as, where
s = the distance needed
a = acceleration due to gravity
u = initial velocity which is v & 2v
v = final velocity which is 0
For the first car with initial velocity, 2v, on substituting into the equation, we have
v² = u² - 2as(1)
0 = 4v - 2as(1)
4v = 2as(1)
2v = as(1), making s(1) subject of formula we have
s(1) = 2v/a
Taking the second car, we have u = v
v² = u² - 2as(2)
0 = v - 2as(2)
v = 2as(2), making s(2) subject of formula, we have
s(2) = v/2a
Not, ratio of s1 : s2 =
2v/a : v/2a
s1/s2 = 2v/a ÷ v/2a
s1/s2 = 2v/a * 2a/v
s1/s2 = 4av/av
s1/s2 = 4/1
Therefore, the ratio of the first car to the second car is 4:1
Please leave a like if it helped you
please hellp!!!!!!!!!!!!!!!!!!!!?
Answer:
the second to last by the north pole
Explanation:
arrangement in which a light ball hangs from a thread and oscillates freely
Answer:
pendulum
hope it helps! please mark me brainliest..
Thank you! have a good day ahead
A student is creating an electromagnet for an investigation. Which feature of the electromagnet will least influence the magnetic force?
A
the material of the core
B
the brand of the battery
С
the number of wire coils
D
the che of the power source
A gold wire that is 1.8 mm in diameter and 15 cm long carries a current of 260 mA. How many electrons per second pass a given cross section of the wire
Answer: 162500000
Explanation:
given data:
wire diameter = 1.8mm
wire length = 15cm
current = 260mA.
electron charge e = [tex]1.6*10^{-19} C[/tex]
Solution:
[tex]I = \frac{q}{t}[/tex]
where:
[tex]I = current\\\\q = charge\\\\t = time \\\\q=It\\\\q= 260mt[/tex]
[tex]q=ne\\\\n = \frac{q}{e} \\\\n= \frac{260*10^{-3} t}{1.6*10^{-19} } \\\\n= 162500000t\\\\\frac{n}{t} = 162500000[/tex]
number of electrons per seconds would be 162500000
which of the following is not a mechanical form of energy?
a. Nuclear
b. Kinetic
c. Spring potential
d. Gravitational potential
Answer:
The answer is Spring Potential
Explanation:
Because all the others are a mechanical form of energy
The Sun's energy comes from which nuclear reaction? O A. Two nuclei joining to form a larger nucleus OB. Two nuclei giving off alpha particles OC. A nucleus splitting to form two or more smaller nuclei D. A nucleus giving off a positron
Answer:
Nuclear Fusion reactions power the Sun and other stars. In a fusion reaction, two light nuclei merge to form a single heavier nucleus. The process releases energy because the total mass of the resulting single nucleus is less than the mass of the two original nuclei.
Explanation:
The sun's energy comes in the form of a nuclear reaction due to the Two nuclei joining to form a larger nucleus. Thus option A is correct.
What is nuclear fusion?A nuclear fusion is a reaction in which 2 or more atomic nuclei combine to form one or more atomic nuclei and is manifested by the release or the absorber of energy.
This is due to the differeces in the nuclear binding energy due to the force of nuclei before and after the reaction. The process releases energy as single declines less than the mass of the original nuclei.
Find out more information about the nuclear reaction.
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You drop a coin off of a building and in lands flat on the ground. It hits with a pressure of 200N/m2. It has a weight of 0.1N. What is the area of the coin?
Answer:
5×10¯⁴ m².
Explanation:
From the question given above, the following data were obtained:
Pressure (P) = 200 N/m²
Weight = Force (F) = 0.1 N
Area (A) =?
Pressure, force and area are related by the following equation:
Pressure (P) = Force (F) / Area (A)
P = F / A
With the above formula, we can obtain the area of the coin as follow:
Pressure (P) = 200 N/m²
Weight = Force (F) = 0.1 N
Area (A) =?
P = F / A
200 = 0.1 / A
Cross multiply
200 × A = 0.1
Divide both side by 200
A = 0.1 / 200
A = 5×10¯⁴ m²
Thus, the area of the coin is 5×10¯⁴ m².
Help! Help!
___ are a primary way to discourage drinking and driving.
A. High prices for alcohol
B. Scare tactics
C. Laws
Answer:
Laws
Explanation:
Laws are a primary way discourage drinking and driving
A primary way to discourage drinking and driving is Law.
What is drinking and driving?The person who takes in alcohol and then drives on the road. This is strictly prohibited.
Laws against the 'drinking and driving' will make people get scared of getting charged or sentenced to jail for some years. Lot of accidents have caused when there were no laws against the action.
Thus, Laws are a primary way to discourage drinking and driving.
Learn more about drinking and driving.
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what must be photographed with an impression before it is moved or cast ?
What is the momentum of a 12 kg ball with velocity of 24 m/s?
Answer:
288 kg.m/sExplanation:
The momentum of an object can be found by using the formula
momentum = mass × velocity
From the question we have
momentum = 12 × 24
We have the final answer as
288 kg.m/sHope this helps you
The electron has the positron as its antiparticle.
A True
B False
rawr goes the dinosaur rawrrrrrrr >:c
Answer:
rawrrrrrrrrrrrrrrrrrr
lol Thank you
Answer:AAAAAAHHHHH scary :c
Explanation:
A submarine window has 1730 N of
force on it, due to water pressing it
with 2.45 atm of pressure. What is
the area of the window?
(Unit = m^2)
As always, keep 3 sig figs.
Enter
Answer:
0.007
Explanation:
A = F/P
Force = 1730
P = 2.45 = 2.47 * 10^5
1730/(2.47*10^5) = 0.007
Answer:
Hi.
The answer to this problem is 0.007
Explanation:
It was correct for Acellus
How to solve it:
P=F/A
Rearrange it for A, plug in the numbers and solve!
A=F/P
F=1,730
P=2.45
The weight of a 0.5 kg object on the surface of Planet X is 20 N. If the radius of the planet is 4 X 106 m, what is its mass?
Answer:
The mass of the Planet X is 9.595 x 10²⁴ kg.
Explanation:
mass of the object, m = 0.5 kg
radius of the Planet X, r = 4 x 10⁶ m
weight of the object, W = F = 20 N
let the mass of the Planet X = mₓ
Apply Newton's gravitational law;
[tex]F = \frac{Gmm_x}{r^2} \\\\m_x = \frac{Fr^2}{Gm} \\\\m_x = \frac{(20)(4\times 10^6)^2}{6.67 \times 10^{-11} \ \times \ 0.5} \\\\m_x = 9.595 \times 10^{24} \ kg[/tex]
Therefore, the mass of the Planet X is 9.595 x 10²⁴ kg.
Help!!
The effects of an increasing BAC are not linked to the passage of time.
A. True
B. False
The statement 'the effects of an increasing BAC are not linked to the passage of time' is False.
What does BAC mean?The abbreviation BAC indicates 'blood alcohol concentration' and it is a measure that allows us to know the amount of alcoholic content.
This value (blood alcohol concentration) is well known to decrease over time.In conclusion, the statement 'the effects of an increasing BAC are not linked to the passage of time' is False.
Learn more about blood alcohol concentration here:
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Hurry need an answer
Answer:
i think b
Explanation:
when a man throws a stone in the direction of maximum range the stone rises to a height of 20m . what is the range and how long is the stone in air
Answer:
50m
Explanation:im just smart thank me later
The range is 80 meter and the stone is 4.04 second in air.
What is projectile?When a particle is hurled obliquely near the surface of the earth, it travels along a curved path while accelerating continuously in the direction of the planet's center (we assume the particle stays close to the surface of the globe). Such a particle's motion is known as projectile motion, and its route is referred to as a projectile.
Given that: maximum height obtained by the projectile; H = 20 m.
Let initial velocity = u
For maximum range:
H = u²/4g
u = √(4gH) = 28 m/s
and the range of the projectile = u²/g = 4H = 4 ×20 m = 80 m.
Total time of flight = √2· u/g = √2 ×28/9.8 = 4.04 second.
Learn more about projectile here:
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HELP ASAP!!! PLEASE!!
Answer:
Explanation:
The weaker force is pulling to direction East(450 newton)
the net force is (500-450=50 newton) and will move toward west ( in 500 newton direction)
Define friction. Prove that tangent of angle of friction is equal to coefficient
of friction.
Answer:
Friction is the force that opposes movement between moving objects.
The angle at which one object starts to slip on the other is directly related to the coefficient. When the two objects are horizontal there is no frictional force. So, the coefficient of static friction is equal to the tangent of the angle at which the objects slide. A similar method can be used to measure μk.
Explanation:
Answer:
brainliest plsssssss
Explanation:
The resistance that one surface or object encounters when moving over another
A boy climbs 12.0m up an apple tree. He picks an apple and throws it horizontally with a velocity of 3.0 m/s. How far forward does the ball go before it hits the ground
Answer:
4.692m
Explanation:
The distance that this boy climbed = 12.0m
The velocity = 3.0m/s
We are to find how far forward this apple goes before it hits the ground.
We have y = 1/2gt²
X = v*t
T = 1.564 seconds
X = 3x1.564
X = 4.692m
Therefore the ball goes a distance of 4.692m forward before it then hits the ground.
What type of telescope did Galileo use to observe Jupiter?
reflector telescope
refractor telescope
radio telescope
latter telescope
Answer:
a refractor telescope
Explanation:
Answer:
a. refractor telescope
HELP ASAP!
Everything on screenshot!
Hydrogen bonds create unusual properties in water. What are they?
Answer:Liquid water is denser than Ice.
Ice float on top of liquid water.
Explanation:
Just trust me
Sample Volume Mass
A 100 ml 100 g
B 80 ml 100 g
C 110 ml 100 g
D 120 ml 100 g
^table
The table shows the volumes of different samples of liquid. Which sample has the greatest DENSITY?
A)
Sample A
B)
Sample B
C)
Sample C
D)
Sample D
Answer:
sample B
Explanation:
The samples given all have the same mass which is 100g but their volume differs significantly.
Density is the mass per unit volume of a substance. The mass is the amount of matter contained in a substance. Volume is the space a body occupies.
Density = [tex]\frac{Mass}{Volume}[/tex]
Density is inversely proportional to volume. The higher the volume the lesser the density provided the mass is constant.
So, the sample with the least volume will have the greatest density value.
This sample is sample B
Answer:
the answer is b
Explanation:
Can someone please explain this?
Explanation:
u = Initial velocity = 20m/s
v = Final velocity = 0m/s
a = Acceleration = -5m/s²
We wish to find s, the displacement of the car.
Using Kinematics, we have v² = u² + 2as.
Therefore (0)² = (20)² + 2(-5)s, and s = 40m.
write the difference between convert and
Concave minores
Approximating Earth's atmosphere as a layer of gas 6.8 km thick, with uniform density 1.3 kg/m3 , calculate the total mass of the atmosphere.
Answer:
The total mass of the atmosphere is 4.508 x 10⁹ kg
Explanation:
Given;
thickness of gas layer, h = 6.8 km
density of Earth's atmosphere, ρ = 1.3 kg/m³
the surface area of Earth is given as 5.10 x 10⁸ km²
Volume of the atmosphere is calculated as;
V = Ah
where;
A is the surface area of Earth
h is the thickness of gas layer
V = (5.10 x 10⁸ km²)(6.8 km)
V = 3.468 x 10⁹ km³
The total mass of the atmosphere is calculated as;
mass = density x volume
m = ρV
m = (1.3 kg/m³)(3.468 x 10⁹ km³)
m = 4.508 x 10⁹ kg
Therefore, the total mass of the atmosphere is 4.508 x 10⁹ kg.