A teacher has two radioactive sources, A and B.
Source A has a longer half-life than source B.
What can be deduced about the nuclei in source A compared with the nuclei
in source B?
Do not refer to isotopes in your answer.
Answer:
The nuclei of source have greater stability than those of source B.
If a train travels 25 miles in 2 hours 15 minutes, what is its average speed in miles per hour? 11. 1 mph 12. 5 mph 10 mph 9. 1 mph.
Answer:
11.1
Explanation:
2 hours 15 mins = 2 1/4 hours
2 1/4 hours = 25 miles
1 hour = 25 ÷ 2 1/4 = 25 ÷ 9/4 = 25 x 4/9 = 11.1 miles
What is the correct definition of rarefaction
Answer:
Explanation:
A decrease in the density of something is rarefaction. ... Most of the time, rarefaction refers to air or other gases becoming less dense. When rarefaction occurs, the particles in a gas become more spread out. You may come across this word in the context of sound waves.
A long-distance runner runs at a constant speed of 4.8 m/s. How long does it take them to run 1.5 km?
Convert km to meters:
1km = 1000 m
1.5 km x 1000 = 1500 m
1500m / 4.8 m/s = 312.5 seconds
312.5 seconds / 60 seconds per minute =5.2 minutes = 5 minutes 12.5 seconds
help me solve please
Answer:
please check the image
Explanation:
I hope this image helps you please follow the steps. Thank you
Answer:
1kg/```````2
Explanation:
solution
3. If John leaves his house to walk his dog and he walks around the block, what is
his distance?
180 Meters
180 Meters
180 Meters
180 Meters
Answer:
180 meters
Explanation:
Consider the schematic of the molecule shown, with two hydrogen atoms, H, bonded to an oxygen atom, O. The angle between the two bonds is 106°. If the bond length r = 0.103 nm long, locate the center of mass of the molecule. The mass mH of the hydrogen atom is 1.008 u, and the mass mO of the oxygen atom is 15.9999 u. (Use a coordinate system centered in the oxygen atom, with the x-axis to the right and the y-axis upward. Give the coordinates of the center of mass in nm.)
The definition of the center of mass allows to find the result for the position of the mass center of more than the H₂O molecule is;
[tex]x_{cm} = 0 \ and \ y_{cm} = 6.9 10^{-3 } nm[/tex]
the concept of center of mass of a system is the point where external forces are applied, it is given by the expression
[tex]\frac{x}{y} =\frac{1}{M_{total}} \sum m_i r_i[/tex]
Where M is the total mass of the systemr_i and m_i sums the position and masses of the element i of the system
In the attachment we have a diagram of the system where the axis and coordinates of the molecules are shown, in this case it is indicated that the origin is in the oxygen atom, so its distance is zero.
[tex]r_{cm} = \frac{1}{2 m + M} \ (2 m r )[/tex] )
They indicate the mass of the hydrogen atom m = 1.008 amu, the bond length r = 0.103 nm and there is an angle 106º between the two hydrogens, therefore the angle from the vertical is:
θ = 106/2 = 53º
Let's find the position of the center of mass for each axis.
x-axis
[tex]x_{cm} = \frac{1}{2m+ M} \ ( m x_1 - m x_2)[/tex]
y-axis
[tex]y_{cm} = \frac{1}{2m + M} \ ( m y_1 + m_2)[/tex]
Let's use trigonometry to find the components of the bond length.
cos θ = [tex]\frac{y}{L}[/tex]
sin θ = [tex]\frac{x}{L}[/tex]
y = L cos θ
x = L sin θ
We substitute.
[tex]x_{cm} = \frac{1}{2m+M} \ (mL (sin 53 + sin (-53)) \\y_{cm} = \frac{1}{2m + M} \ ( mL cos 53 + mL sin 53)[/tex]
we use.
sin θ = - sin -θ
cos θ = cos -θ
Let's calculate.
[tex]x_{cm} = 0 \\y_{cm} = \frac{1}{2 \ 1.008 + 15.9999} \ ( 2 \ 1.008 \ 0.103 cos 53)[/tex]
We see that the center of mass is on the x axis and at a distance from the y-axis of 6.9 10-3 nm
In conclusion using the definition of the center of mass we can find the result for the position of the center of mass of the H₂O molecule is;
[tex]x_{cm}=0[/tex] and [tex]y_{cm}[/tex]cm = 6.9 10⁻³ nm
Learn more here: brainly.com/question/8662931
Explain why we draw straight lines to show rays of light?
Answer:
Because light always travels in straight line.
Explanation:
The fact that light travels can be demonstrated by putting an object in its path. If the object is opaque the result is a degree of blackness on the other side of it which is due to the absence of the light. ... As light does appear to travel in straight lines then light is usually modelled as straight lines in drawings.
Hope this helps :)
#Followformore
Calculate the force applied if 100 N/m² pressure is exerted over the area of 0.2m²
Answer: 100 pascals times 0.2 m^2= 20 N force is applied.
Explanation:
how many tries did it take to invent the lightbulb?
why the max Static frictional force is a Little bit bigger than the sliding frictional force
Part IV Objects on an incline w/ Tension + Friction
1. A small 63 kg sleigh is pulled by a rein attached to horse up a 15'angle hill to the
horizontal. The tension of the rein is 510 N. The coefficient of kinetic friction is
0.25
a. What is the normal force that the sleigh exerts on the hill?
b. What are the magnitude and direction of the sleigh's acceleration?
(a) The normal force on the sleigh is 596.36 N.
(b) The magnitude and direction of acceleration of the sleigh is 3.2 m/s² upwards.
The given parameters;
mass of the sleigh, m = 63 kginclination of the hill, θ = 15⁰tension on the rein, F = 510 Ncoefficient of friction, μ = 0.25The normal force on the sleigh is calculated as follows;
[tex]F_n = mg \times cos(\theta)\\\\F_n = 63 \times 9.8 \times cos(15)\\\\F_n = 596.36 \ N[/tex]
The magnitude and direction of acceleration of the sleigh is calculated as follows;
[tex]\Sigma F= ma\\\\F - mgsin(\theta) - F_f = ma\\\\F - mgsin(\theta) - \mu F_n = ma\\\\510\ - \ 63 \times 9.8 \times sin15 \ -\ 0.25\times 596.36 = 63a\\\\201 .11 = 63a\\\\a = \frac{201.11}{63} \\\\a = 3.2 \ m/s^2 \ upwards[/tex]
Learn more here:https://brainly.com/question/19133846
Anna used a rock to drive a peg into the ground to put up her tent. If the rock applied a 9. 5 N force in 0. 50 s, what is the impulse on the peg? 4. 8 N • s 9. 5 N • s 10 N • s 19 N • s.
Answer:
4.8 N*s
Explanation:
P = F*t
P = Impulse/ momentum
F = force (Newtons)
t = time (seconds)
P = 9.5N*0.5s
P = 4.75 N*s
Hi there!
[tex]\large\boxed{I = 4.8 N}[/tex]
Impulse = Force (N) × Time (s)
We can also express this as:
I = Δp = Ft
Plug in the given values:
I = 9.5(.50) = 4.75 ≈ 4.8 Ns
1 point
What is the acceleration of a bicyclist moving at a constant speed of 10
m/s for 5 seconds? *
PLEASE HELP HURRY
Answer:
0
Explanation:
The bicyclist is not speeding up or slowing down so there is no acceleration.
I need help making a chart (preferably a line graph) with this data. I'm not sure how to show that it will be a linear line in a graph. If you don't have excel can you explain to me how to do it.
note: these datasets are separate and arent related
Spring Constant (N/m) Displacement (m)
100 0.5m
300 0.167m
500 0.1m
700 0.071m
Applied force (N) Displacement (m)
20 0.2m
30 0.3m
50 0.5m
70 0.7m
Answer:
the graph plotted based on your data, you did not mention what are the variables on the x-axis and y- axis . and the graphs can be three small graphs of different material of one quality i.e. thickness or length
hope it helps
Explanation:
a
(2) A 800 g block is pushed up an inclined plane (angled at 18°) with a velocity of 11.8 m/s. The first block slides up the
incline a distance of 2.2 m and strikes a second block with a mass of 300 g also moving at 3.4 m/s up the incline.
The two blocks hit and stick together. Determine the following:
(i) The maximum vertical height of the two blocks when they stop.
(ii) The time needed for the blocks to reach the bottom of the incline after the moment of impact.
(u = 0.19)
this is my attachment answer hope it's helpful to you
How is "speed" defined in terms of physics?
Explanation:
In everyday use and in kinematics, the speed of an object is the magnitude of the rate of change of its position with time or the magnitude of the change of its position per unit of time; it is thus a scalar quantity.
Which object has the most thermal energy?
A. A 6 kg rock at 10°C
B. A 10 kg rock at 10°C
C. A6 kg rock at 15°C
D. A 10 kg rock at 15°C
Answer:
D is the answer
Explanation:
D is the most highest one so
the answer is D
Answer:
10 kg rock at 15 degrees celcius
how do astronomers determine the origin of a meteorite that reaches earth?
Researchers begin their study by identifying the rock type and then dating the meteorite
Explanation:
.
solve for the BMI weight 58kg Height 1.61
Answer:
Explanation:
BMI= weight/(height × height) ; weight in kilogram and height in metter
= 58kg / (1.61m × 1.61m )
= (58/ 2.5921) kg/[tex]m^{2}[/tex]
= 22.375 kg/[tex]m^{2}[/tex]
≈ 22.4 kg/[tex]m^{2}[/tex]
1 point
A roller coaster is 20 m high and traveling 11 m/s. If the roller coaster has a
mass of 150 kg, what is its total energy? (only put the number, no units or
commas)
Answer:
ETotal=38505J
Explanation:
Known values:
m=150kg
h=20m
v=11m/s
KE=mv^2/2
PE=mgh
ETotal=PE+KE
KE=(150(11^2))/2
KE=9075
PE=150(9.81)(20)
PE=29430
ETotal=9075+29430
ETotal=38505J
Find the velocity of a body of mass 100 g having kinetic energy of 20 J.
Answer:
Explanation:
Let v be the velocity of object ,
Given that mass of object , m=100 g=
1000
100
kg=0.1 kg
& kinetic energy of object =20 J
K.E =
2
1
mv
2
20=
2
1
×0.1v
2
⟹v
2
=400
⟹v=20 m/s
A force acts on an object. Which option describes an action that could prevent the object from moving
Answer:
Friction or tension
Explanation:
Friction stops an object from moving in the presence of force
a box takes 350 N to start moving the coefficient of static friction is 0.35. what is the weight of the box?
Answer:
101.937 kg
Explanation:
The force needed to get the box moving must just cancel the static friction force:
F = µsmg = 0.35•m•9.81 = 350 ---> m = 350 / (0.35•9.81) = 101.937 kg
Again, with units shown, and using 1 N = 1 kg•m/s2:
0.35•m•9.81(m/s2) = 350 N
solving for m:
m = 350 N / (0.35•9.81 m/s2) = (350 kg•m/s2) / (3.434 m/s2 ) = 101.937 kg
______________________
(Hope this helps can I pls have brainlist (crown)☺️
what is the chemical and physical changes if making a starchs
Answer:
Chemical modification of starch is based on the chemical reactivity of the constituent glucose monomers which are polyhydroxyl and can undergo several reactions. Starch can undergo reactions such as hydrolysis, esterification, etherification and oxidation.
Explanation:
Hope this helps!
SOMEONE PLEASE HELP ME IM GOING INSANE 4 Select the correct answer. A satellite completes one revolution of a planet in almost exactly one hour. At the end of one hour, the satellite has traveled 2.0 x 107 meters and is only 10 meters away from its starting point. What is the numerical value of the satellite's average velocity after that one hour? O A. -3.77 x 10-2 meters/second OB. -2.77 x 10-3 meters/second OC. -2.62 x 10-2 meters/second D. -5.55 x 103 meters/second
Hi there!
Since we are dealing with such large distances, we can approximate.
Recall that the equation for speed is:
displacement / time = velocity
OR:
d/t = v
Begin by converting one hour to seconds:
1 hr = 3600 sec
Now, we can solve for velocity:
(-2.0 × 10⁷) / 3600 = -5555.6 m/s ⇒ D: -5.55 × 10³ m/s
a force that is at rest or moves in at a constant speed and in a constant direction is called a what force
The question is fishing for "balanced force".
But the description in the question is terrible.
What mass M will cause this system accelerate e 0.75 m/s²?
Answer:
5.54 [kg].
Explanation:
1) if m₁=6; g=9.81; a=0.75 and m₂ - reqired mass, then
2) it is possible to write: m₁*a=m₁*g-m₂*g, and
3) [tex]m_2=\frac{m_1(g-a)}{g}; \ => \ m_2=\frac{6*(9.81-0.75)}{9.81}=5.54[kg].[/tex]
Which statement indicates that motion has occurred?
A. The reference point has changed.
B. The position of the object has changed.
C.The object has not changed.
D. The object being described has changed
hannah drove 360 mi in 5.2 hours. What was her average speed?