What is a half-life?
A. the amount of time it takes for 25% of a radioactive isotope sample to decay
B. half of the time it takes for an organism to die
C. the amount of time it takes for a radioactive isotope to become stable
D. the amount of time it takes for half of a radioactive isotope sample to decay
Answer:
option D is correct
Explanation:
Answer: “ D ”
the amount of time it takes for half of a radioactive isotope sample to decay
The diagram shows our solar system. name planet 4
Answer:
mars
Explanation:
it is the fourth planet of the solar system
Why does the weather change during an eclipse? help me
Answer:
here`s your answer
Winds often slow down during an eclipse as the atmosphere temporarily settles. Heating causes the atmosphere to mix and bubble, just like a pot of water on the stove. As it warms, the water level in the pot rises because warm objects, including water, expand. In the case of the atmosphere, it also expands when heated.
Explanation:
A car travels at a constant speed up a ramp making an angle of 28 degrees with the horizontal component of velocity is 40 kmh^-1, find the vertical and horizontal component of velocity.
Answer:
Vx = 35.31 [km/h]
Vy = 18.77 [km/h]
Explanation:
In order to solve this problem, we must decompose the velocity component by means of the angle of 28° using the cosine function of the angle.
[tex]v_{x} = 40*cos(28)\\V_{x} = 35.31 [km/h][/tex]
In order to find the vertical component, we must use the sine function of the angle.
[tex]V_{y}=40*sin(28)\\V_{y} = 18.77 [km/h][/tex]
Which atmospheric gas is used by plants and given off by animals? A. Carbon dioxide. B. Nitrogen C. Oxygen D. Argon
Answer:
A
Explanation:
Answer:
i think it is B
Explanation:
plants and humans have a cycle thing humans breath out carbon dioxide and plants absorb that and released it as oxygen and animals and humans breath in
Which of these results in kinetic energy of an object? position motion mass volume
Answer:
Motion
Explanation:
I just took the test :)
P.S. Can I please get a brainliest (look at my account to see what i do with the points :p)
Kinetic energy is the energy that set an object or body in motion. Motion result in kinetic energy.
What is kinetic energy?Kinetic energy is the energy required to set an object in motion.
It is the energy present in a moving body. This involve the movement of an object from one place to another as it is found in a moving ball or car.
Therefore, motion result in kinetic energy.
Learn more about kinetic energy from the link below.
https://brainly.com/question/8101588
Exercise to solve
1) Determine the magnitude of the electrostatic attractive force between two charges of 2 µc and -6 µC respectively if they are separated by a distance of 2 mm
2) Determine the magnitude of the electrostatic attractive force between two charges of 6 µC and -8uC respectively if they are separated by a distance of 8 cm
Briefly explain in a minimum of five lines and a maximum of 8 lines
Dalton’s theory states that atoms are the smallest possible parts of elements. In a chemical reaction, atoms will
rearrange and form new substances with new properties.
change form into completely new atoms with new properties.
be destroyed and remade into new substances.
be turned completely into energy.
An atom’s emission of light with a specific amount of energy confirms that
Answer:
A.REARRANGED AND FORM NEW SUBSTANCES WITH NEW PROPERTIES
Explanation:
it is dangerous to stand near the railway leak when train passing by,why?
Answer:
Because a person may be pulled in the direction of the moving train. Thereby causing accident
Explanation:
According to Daniel Bernoulli's theorem, he was widely known as a Mathematician. He stated that due to the higher velocity of a moving train, there is higher kinetic energy in terms of volume around it, while the air pressure between the person and the train becomes lower.
As a result, a person near a moving train may be pulled in the direction of the moving train. Thereby causing accidents that may lead to death.
A force of 200N acts at an angle of 140° with respect to the positive x- direction. determine the components of this force in the x- and y- direction
Answer:
The components of the force in the x and y-direction are -153.21 N and 128.56 N respectively.
Explanation:
Rectangular components of a vector
Given a vector [tex]\vec F[/tex] as an ordered pair (f,θ), where f is the magnitude of the vector and θ is the angle it forms with the positive x-direction, the rectangular components of the vector are given by:
[tex]F_x=f.\cos\theta[/tex]
[tex]F_y=f.\sin\theta[/tex]
The force of f=200N forms an angle of θ=140°. The components of the force are:
[tex]F_x=200.\cos 140^\circ[/tex]
Calculating:
[tex]F_x=-153.21~N[/tex]
[tex]F_y=200.\sin 140^\circ[/tex]
[tex]F_y=128.56~N[/tex]
The components of the force in the x and y-direction are -153.21 N and 128.56 N respectively.
Three persons wants to push a wheel cart in the direction marked x in Fig. The two person push with horizontal forces F1 and F2 as F1 = 45 N 70degree And F2 = 75 N , 20 Degree (a) Find the magnitude and direction of the force that third person should exert to stop this cart. You can ignore the effects of friction. (b) If the third person exerts the force found in part (a), the cart accelerates at 200 m/S2 in the (+) x-direction. What is the weight of the cart
Answer:
a) F₃ = 109.5 N , θ₃ = 38.35, b) m = 0.429 kg
Explanation:
For this force addition exercise, let's decompose the forces into a coordinate system
strength 1
cos 70 = F₁ₓ / F₁
sin 70 = [tex]F_{1y}[/tex] / F₁
F₁ₓ = F₁ cos 70
F_{1y} = F₁ sin 70
F₁ₓ = 45 cos 70 = 15.39 N
F_{1y} = 45 sin70 = 42.29 N
Strength 2
cos 20 = F₂ₓ / F₂
sin 20 = F_{2y} / F₂
F₂ₓ = F₂ cos 20
F_{2y} = F₂ sin20
F₂ₓ = 75 cos 20 = 70.48 N
F_{2y} = 75 sin 20 = 25.65 N
a) in the first part we are asked to find the magnitude of force 3 so that the body is in equilibrium
X axis
∑ Fₓ = 0
F₁ₓ + F₂ₓ + F₃ₓ = 0
F₃ₓ = - F₁ₓ - F₂ₓ
F₃ₓ = - 15.39 - 70.48
F₃ₓ = - 85.87 N
Y Axis
∑ F_{y} = 0
F_{1y} + F_{2y} +F_{3y} = 0
F_{3y} = - F_{1y} -F_{2y}
F_{3y} = - 42.29 - 25.65
F_{3y} = - 67.94 N
the magnitude of this force can be found using the Pythagorean theorem
F₃ = √ (F₃ₓ² + F_{3y}^2)
F₃ = √ (85.87² + 67.94²)
F₃ = 109.5 N
The direction of this force can be found using trigonometry
tan θ = F₃ = [tex]F_{3y}[/tex] / F₃ₓ
θ₃ = Tan⁻¹ (67.94 / (85.87))
θ₃ = 38.35º
since the two vectors are negative this angle is in the third quadrant, measured from the positive side of the x axis is
θ₃ = 180 + 38.53
θ₃ = 218.35º
b) I think you have an error in your statement, we have two possibilities:
1) If we eliminate the third force, what is the mass
it should say: "if we apply the third force force ...", they ask that we find the masses of the vehicle, let's use Newton's second law
X axis
F₁ₓ + F₂ₓ = m a
15.39 + 70.48 = m 200
m = 85.87 / 200
m = 0.429 kg
2) If the force F3 is in the first quadrant
F1x + F2x + F3x = m a
m = (15.39 + 70.48 + 85.87) / 200
m = 0.8587 kg
how much heat is necessary to warm 500g of water from 20°c to 65°c
Explanation:
so sorry
don't know but please mark me as brainliest please
Why does everyone trust gravity?(Explained)(Will Give Brainliest)
Answer:
Because gravity makes you able to stand and move around
Gravity can't fail
it can fail only in astronuts camp and in space
Explanation:
✌❤
Yh....
:)
What is the kinetic energy of a 72.2 kg cheetah moving at a velocity of 25.9 m/s?
935 J
5450 J
48,400 J
24,200 J
Given:
Mass of cheetah (m) = 72.2 kg
Speed of cheetah (v) = 25.9 m/s
Equation:
[tex] \rm KE = \dfrac{1}{2} mv^2[/tex]
Answer:
By substituting values in the equation, we get:
[tex] \rm KE = \dfrac{1}{2} \times 72.2 \times (25.9)^2 \\ \\ \rm = \dfrac{1}{2} \times 72.2 \times 670.81 \\ \\ \rm = 36.1 \times 670.81 \\ \\ \rm = 24,216.241 \\ \\ \rm \approx 24,200 \ J[/tex]
[tex] \therefore [/tex] Kinetic energy of cheetah = 24,200 J
In June 21 are there more hours of daylight in San Francisco or the equator explain
Answer:
There would be more hours of sunlight at the equator
can someone write me an expository essay about bullying amongst teens pleasee
Answer
bullying is not something that should be allowed in school or anywhere at that matter because by being bullied can lead to many things such as harm attempts and risks of kids lives. bullying is always impacted by kids when they're small and ends up making their lives a miserable buy bullying kids and adults too no matter what age what end up turning either suicidal or trying to face drugs thinking that it's going to help period and we lose lives every day many many lives because of the things that people say and do to each other and that's not right at all whatsoever. people need to be able to live their lives the way they wants to without having to think about is somebody's going to believe them because of the way they look the way they were their clothes and stuff like that. We were made us a certain way not for us to believe one another and harm each other. but it's also not good for our mental and emotional health because of later on we're not going to be stable because we're always pressing ourselves about how we look. and there's not only in person bullying but also cyberbullying and if you look up online you'll find out that in 2018 student was the highest awareness of cyberbullying in all the countries people commit different types of s. u. I. c. I. d. e. because of that and I feel like nobody cares about that but those are people's lives and people lose their loved ones because of bullying. people don't believe that other people matter but in the end we all do and we all should be able to live our lives fully.
A scientific ____ must be testable and capable of being proven false.
Answer:
hypothesis
Explanation: a hypothesis is a guess or a thought meaning it can be true but it might not be
Answer:
capable of being proven wrong.
Explanation:
You can't not be right all the time
When the force at the ends of a bar pushes rather than pulls, the bar experiences
Answer:
Compression
Explanation:
Force is defined as a push or pull on any object. Now, Force could either be in Compression or tension which are the push and pull that allow overhead bridges to remain erect after many years.
Now, Compression is a force that compresses objects together. Meanwhile, Tension is the opposite of compression and it is the force that pulls objects apart.
for f(x)=2x1 and g (x)=x2-7,find (f-g)(x)
Your f(x) value is a little ambiguous, so I am assuming the value of f(x)=2x-1
Answer:
(f-g)(x) = 2x-x²+6
Explanation:
f(x)=2x-1
g(x)=x²-7
(f-g)(x)=f(x)-g(x)
= (2x-1)-(x²-7)
= 2x-1-x²+7
= 2x-x²+6
Therefore,
(f-g)(x) = 2x-x²+6
I WILL MARK YOU AS BRAINLIEST IF RIGHT The fastest pitch ever recorded in MLB was thrown by Aroldis Chapman at 5 points 105.1 mph . If the 0.145 kg baseball accelerated 96 m/s / s , how much force did Chapman apply to the ball? Round your answer to the nearest whole number
Answer: The force was 13.92 Newtons.
Explanation:
First, let's recall the second Newton's law:
The net force is equal to the mass times the acceleration, or:
F = m*a
where:
F = force
m = mass
a = acceleration.
When the player hits the ball with the bat, he applies a force that accelerates the ball for a small period of time, that increases greatly the speed of the ball.
In this case, we know that:
the mass of the ball is 0.145 kg
The acceleration of the ball is 96m/s^2
Then we can input those values in the above equation to find the force.
F = 0.145kg*96m/s^2 = 13.92 N
The force was 13.92 Newtons.
Assuming a release of 173 MeV per fission reaction, calculate how many reactions must occur per second to produce a power output of 170 MW .
Answer:
The number of reaction that must occur is 6.142 x 10¹⁸ reactions / second
Explanation:
Given;
energy released by the fission reaction, E = 173 MeV
power output, P = 170 MW
Convert the energy released by the fission reaction to Joules;
= 173 x 10⁶ x 1.6 x 10⁻¹⁹ J = 2.768 x 10⁻¹¹ J
Convert the output power to joules per second;
= 170 x 10⁶ J/s
The number of reactions per second that must occur is given by;
[tex]= \frac{170*10^6 \ J/s}{2.768*10^{-11} J/reaction} = 6.142 *10^{18} \ reaction/second[/tex]
Therefore, the number of reaction that must occur is 6.142 x 10¹⁸ reactions / second
An object has an acceleration of 18 m/s/s. If the mass of this object were tripled (with no change in its net force), then its new acceleration would be
Answer: 6
If the mass of this object were tripled (with no change in its net force) =>Its acceleration will decrease by 3 times
=> the new acceleration would be: 18/3 = 6(m/s²)
Explanation:
A soccer ball is kicked from the ground with a velocity of 30m/s directed at an angle of 45 degrees with respect to horizontal. Resolve this velocity vector into horizontal and Vertical components
Answer:
Vertical = 21.2 m/s
Horizontal = 21.2 m/s
Explanation:
For the vertical component:
sin (45) = v/30
sin (45) x 30 = v
21.2 m/s = v
For the horizontal component:
cos (45) = h/30
cos (45) x 30 = h
21.2 m/s = h
When an astronaut with a mass of 55 Kg goes from Earth to the Moon, how much does their weight change? Answer in N OR in Pounds. gmoon= 1.62m/s2, gearth = 9.8m/s2
PHYSICS
mass = 55 kg
gravitation earth = 9,8 m/s²
gravitation moon = 1,62 m/s²
Weight Change = ______?
Answer :
1) Earth
[tex]w = m \times g[/tex]
w = 55 × 9,8
w = 539 N
2) Moon
[tex]w \: = m \times g[/tex]
w = 55 × 1,62
w = 89.1 N
If a point on the edge of a wheel 2 m in radius is accelerating at 2 m/s2, what is the angular acceleration of the wheel?
Answer:
[tex]\alpha =1\ rad/s^2[/tex]
Explanation:
It is given that,
The radius of a wheel, r = 2 m
Tangential acceleration of the wheel, [tex]a=2\ m/s^2[/tex]
We need to find the angular acceleration of the wheel. We know that the relation between angular and tangential acceleration is given by :
[tex]a=\alpha r\\\\\alpha =\dfrac{a}{r}\\\\\alpha =\dfrac{2}{2}\\\\\alpha =1\ rad/s^2[/tex]
So, the angular acceleration of the wheel is [tex]1\ rad/s^2[/tex].
How can a systematic error affect the reported data?
Answer:
A systematic error may result in a high degree of precision.
A systematic error will likely result in poor accuracy
Explanation:
It's what my work gave me when I got it wrong
Calculate the total energy of 2.0 kg object moving horizontally at 10 m/s 50meters above the surface.
1080 J
2 00 J
1 00 J
10. J
Answer:
1080J
Explanation:
Given parameters:
Mass of object = 2kg
Velocity = 10m/s
Height = 50m
Unknown:
Total energy = ?
Solution:
The total energy of the moving object is obtainable by summing the kinetic and potential energy;
Total energy = P.E + K.E
P.E is the potential energy = mgh
K.E is the kinetic energy = [tex]\frac{1}{2}[/tex]mv²
Now insert the parameters and solve;
Total energy = mgh + [tex]\frac{1}{2}[/tex]mv²
m is the mass
g is the acceleration due to gravity
h is the height
v is the velocity
Total energy = (2 x 9.8 x 50) + ( [tex]\frac{1}{2}[/tex] x 2 x 10²)
Total energy = 980 + 100 = 1080J
A horizontal spring required a force of 1.0 N to compress it 0.1 m. How much work is required to stretch the spring 0.4 m?
Answer:
0.5JExplanation:
given data
Force applied F= 1N
extension e= 0.1m
let us find the spring constant first
applying
F=ke
k=F/e
k=1/0.1
k=10N/m
Step two:
Required is the work done
we know that the expression/formula for the work done by a spring is given as
Wd=1/2kx^2
x=0.4m
substitute
Wd= 1/2*10*0.4^2
Wd=0.5*10*0.16
Wd=0.5J
NEED A PHYSICS EXPERT TO HELP ME PLS
I've been stuck on this for two hours:
Water flows steadily from an open tank as shown in the figure. (Figure 1)The elevation of point 1 is 10.0 m , and the elevation of points 2 and 3 is 2.00 m . The cross-sectional area at point 2 is 4.80×10−2 m2 ; at point 3, where the water is discharged, it is 1.60×10−2 m2 . The cross-sectional area of the tank is very large compared with the cross-sectional area of the pipe.
Assuming that Bernoulli's equation applies, compute the volume of water ΔV that flows across the exit of the pipe in 1.00 s . In other words, find the discharge rate ΔV/Δt.
Express your answer numerically in cubic meters per second.
The discharge rate of water (Q) that flows across the exit of the pipe in 1.00 seconds is 0.200 [tex]m^3/s[/tex].
Given the following data:
Elevation of point 1 = 10.0 mElevation of point 2 = 2.00 mElevation of point 3 = 2.00 mCross-sectional area at point 2 = [tex]4.80\times 10^{-2} \;m^2[/tex]Cross-sectional area at point 3 = [tex]1.60\times 10^{-2} \;m^2[/tex]To find the discharge rate of water (Q) that flows across the exit of the pipe in 1.00 seconds assuming that Bernoulli's equation applies:
In this exercise, we would apply Torricelli's Law, which states that the speed of the efflux in an apparatus, under the force of gravity is directly proportional to the square root of the height of the fluid above it.
Mathematically, Torricelli's Law is given by the formula:
[tex]V =\sqrt{2gh}[/tex]
Where:
g is the acceleration due to gravity.h is the height of the apparatus.V is the speed of liquid.Substituting the given parameters into the formula, we have;
[tex]V =\sqrt{2 \times 9.8 (10-2)}\\\\V =\sqrt{19.6 (8)}[/tex]
Speed, V = 12.52 m/s
Now, we can find the discharge rate of the pipe:
[tex]Q = V \times A\\\\Q = 12.52 \times 1.60\times 10^{-2}[/tex]
Discharge rate, Q = 0.200 [tex]m^3/s[/tex]
Read more: https://brainly.com/question/18320053
) A friend of yours complains that he often has lower back pain. One day while he picks up a package, you notice he bends at his hips rather than keeping his back straight and bending his knees. Assume he pivots at the hips so that his spine is horizontal. His back muscles then exert a force at 48 cm away from the hips at 13.5 degrees above the horizontal (directed slightly up and to the left in the picture shown). The weight of his upper body is 560 N, and his center of mass is 38 cm from the hips. Draw a force diagram of the spine. What total force is exerted by the back muscle when he picks up a 10 kg package at 82 cm from the hips? Extra credit: Find the force exerted by the hips on the spine/pelvis
Answer:
Explanation:
Please see the figure attached for free body diagram .
Taking torque about the hip joint ,
560 x 38 + 100 x 82 = F sin13.5 x 48
21280 + 8200 = 11.2 F
F = 2632.14 N .
Force exerted by the hip on the spine = 2632.14 N .