Answer:
Q1: (a)
[tex]1cm \: = 10 {}^{ - 2}m[/tex]
so
[tex]45 \times {10}^{ - 2} m[/tex]
Q2:
[tex]1km = 10 {}^{3} m \\ 6378km \times {10}^{ 3} [/tex]
this is the radius in meter
diameter = 2r
in this i don't know which choice is the right answer
Q3:
[tex]1gram = \: {10}^{ - 3} kg[/tex]
so
[tex]250 \times {10}^{ - 3} = 2.5 \times {10}^{ - 1} kg[/tex]
again there is no correct answer
Problem Solving: Show your solution:
Calculate the wavelengths of the following electromagnetic waves.
a) Microwave in an oven with a frequency of 2.45 GHz.
b) Radio waves used by submarines with a frequency of 24 kHz
Answer:
(a) λ = 0.1224 m
(b) λ = 12500 m = 12.5 km
Explanation:
The wavelength can be calculated with the help of the frequency of the waves. The formula utilized for this purpose is given as follows:
[tex]\lambda = \frac{c}{f}[/tex]
where,
c = speed of light = 3 x 10⁸ m/s
λ = wavelength of the wave
f = frequency of the wave
(a)
f = 2.45 GHz = 2.45 x 10⁹ Hz
λ = ?
Therefore,
[tex]\lambda = \frac{3\ x\ 10^{8}\ m/s}{2.45\ x\ 10^{9}\ Hz}\\[/tex]
λ = 0.1224 m
(b)
f = 24 KHz = 2.45 x 10³ Hz
λ = ?
Therefore,
[tex]\lambda = \frac{3\ x\ 10^{8}\ m/s}{24\ x\ 10^{3}\ Hz}\\[/tex]
λ = 12500 m = 12.5 km
In designing buildings to be erected in an area prone to earthquakes, what relationship should the designer try to achieve between the natural frequency of the building and the typical earthquake frequencies?
A) The natural frequency of the building should be exactly the same as typical earthquake frequencies.
B) The natural frequency of the building should be almost the same as typical earthquake frequencies but slightly lower
C) The natural frequency of the building should be very different frem typical earthquake frequencies
D) The natural frequency of the building should be almost the same as typical earthquake frequencies but slightly higher.
Answer:
C) The natural frequency of the building should be very different from typical earthquake frequencies
Explanation:
We shall apply the concept of resonance in this problem .
When a body is applied an external harmonic force ( forced vibration) such that natural frequency of body is equal to frequency of external force or periodicity of external force , the body vibrates under resonance ie its amplitude of vibration becomes very high .
In the present case if natural frequency of building becomes equal to the earthquake's frequency ( external force ) , the building will start vibrating with maximum amplitude , resulting into quick collapse of the whole building . So to avoid this situation , natural frequency of building should be very different from typical earthquake frequencies .
Chocolate milk contains more than one type of component. Therefore, it 1 point
is not a(n)
substance
Answer:
Homogeneous.
Explanation:
Mixture can be defined as a combination of two or more substances present in varied proportion where each materials are distinct and visibly seen by naked eyes.
In Science, there are two (2) main types of mixture and these are;
I. A homogeneous mixture: it can be defined as any liquid, solid or gaseous mixture which has an identical or uniform composition and properties throughout any given sample of the mixture. In Chemistry, all solutions are considered to be a homogeneous mixture. For example, aqueous hydrogen chloride is a homogeneous mixture of water and hydrogen chloride.
II. A heterogenous mixture: it can be defined as any mixture which has a different or non-uniform composition and properties throughout any given sample of the mixture. This ultimately implies that, the constituents of a heterogenous mixture always remain separate in the sample and as such comprises of two or more phases.
Since the chocolate milk contains more than one type of component. Therefore, it is not a homogeneous substance but a heterogenous substance.
A 3 kg block is attached to a spring of spring constant k = 250 N/m. The block is pulled to a maximum distance (amplitude) of 8 cm What is the value of the spring force when the block is at 8 cm?
Answer:
20 N
Explanation:
From the question given above, the following data were obtained:
Mass (m) of block = 3 Kg
Spring constant (K) = 250 N/m
Extention (e) = 8 cm
Force (F) =?
Next, we shall convert 8 cm to m. This can be obtained as follow:
100 cm = 1 m
Therefore,
8 cm = 8 cm × 1 m / 100 cm
8 cm = 0.08 m
Thus, 8 cm is equivalent to 0.08 m.
Finally, we shall determine the force when the block is at 8 cm (i.e 0.08 m). This can be obtained as follow:
Spring constant (K) = 250 N/m
Extention (e) = 0.08 m
Force (F) =?
F = Ke
F = 250 × 0.08
F = 20 N
Thus, the force is 20 N.
Solve each of the following problems to 3 sig figs and correct Sl units, showing all work.
1. A cart with a mass of 45.0 kg is being pulled to the right with a force of 250 N giving it an
acceleration of 1.30 m/s2. The wheels of the cart are locked and the cart must be dragged.
a) Draw a free body diagram of the cart.
b) Calculate the net force acting on the cart.
c) Create a force table and fill it in.
d) Find the coefficient of kinetic friction.
Answer:
every number to 3 sf = 1) 45.0 2) 250 3) 1.30
Explanation:
your welcome :)
find the volume of an object with a density of 3.2 g/mL and a mass of 12 g.
What relationship must exist between an applied force and the velocity of a moving object if uniform circular motion is to result?
Answer:
See explanation
Explanation:
Centripetal force is defined as the inward force required to keep an object moving with a constant speed in a circular path.
The magnitude of this force depends on the mass of the object, radius of the object and the velocity of the body.
So we can write;
F = mv^2/r
There are two different isotopes; X and Y, both contain the same number of radioactive substances. If sample X
has a longer half-life than Y, compare their rate of radioactive decay.
O A. Rate does not depend on half-life
B. Both of their rates are equal
O C. X has a smaller rate than Y
O D. X has a greater rate than Y
Answer:
Half life refers to the time for 1/2 of the radioactive atoms to decay.
Suppose that X has a half life of 10 days and Y has a half life of 20 days
If both start out with 1000 radioactive atoms then after 20 days
X would have 250 radioactive atoms and Y would have 500 atoms
The rate of decay is greater for the shorter half life:
In the example given X must have the smaller rate of decay because it has a longer half life.
A jogger takes 30 s to run a total distance of 200 m by running 150 m [E] and then 50 m [W]. (a)
Calculate the jogger’s average speed (b) Calculate the jogger’s average velocity
Answer:
(a) 6.67 m/s (b) 3.33 m/s
Explanation:
if i understood your question correctly, the jogger goes 150m east before going in the opposite direction west for 50m. (see diagram)
in avg speed, we use the total distance (150m + 50m = 200m) and total time (30s)
v = d/t =200/30 =6.67 m/s
in avg velocity, we use the total displacement (150m - 50m = 100m) and total time (30s)
v= d/t = 100/30 = 3.33 m/s
calculate the magnitude and the direction of the resultant forces
answer:
resultant = 127.65 in the positive direction
explanation:
F1 = 50N , F2 = 40N, f3 = 55N , f4 = 60N
Fy = 50 sin 50 = 50 × -0.26 = -13
Fx = 40 cos 0 = 40×1 = 40
fx = 55 cos 25 = 55×0.99 = 54.45
Fy = 60 sin 70 = 60 × 0.77 = 46.2
resultant = -13+40+54.45+46.2 = 127.65 in the positive direction
A spring stretches by 15cm when a mass of 300g hangs down from it,if the spring is then stretched an additional 10cm and released, calculate;the spring constant,the angular velocity, amplitude of oscillation, maximum velocity, maximum acceleration of the mass,period, frequency
Answer:
0.1 m
Explanation:
It is given that,
Mass of the object, m = 350 g = 0.35 kg
Spring constant of the spring, k = 5.2 N/m
Amplitude of the oscillation, A = 10 cm = 0.1 m
Frequency of a spring mass system is given by :
Time period:
A potato with a mass of 0.25kg is resting on a table. Calculate the force that the potato exerts on the Earth.
Answer:
F = 2.45 [N]
Explanation:
The force that the potato exerts on the Earth is equal to the product of the potato mass by gravitational acceleration.
[tex]F=m*g[/tex]
where:
m = mass = 0.25 [kg]
g = gravity acceleration = 9.81 [m/s²]
[tex]F=0.25*9.81\\F=2.45[N][/tex]
I want you to think about each of these scenarios, what do you think will happen after? I just want you to think about it, and write a little about what is going to happen.
2. A truck is moving at 20 mph. Your car is standing still at a light and the truck crashes into you before the driver has a chance to step on the brakes.
3. You are driving your car at 20 mph. A bicycle right ahead of you suddenly stops and you crash into it before you have a chance to step on the brakes.
4. A bicycle is moving at 20 mph. Your car is stopped for a light and the bicycle crashes into you.
These three bulbs are powered by the battery. What will happen if the middle light burns out? A. The two other bulbs will go out. B. The two other bulbs will stay on. C. Just the bulb closest to the battery will stay on. D. Just the bulb farthest from the battery will stay on.
Answer:
C
Explanation:
A person weighs 60kg. Calculate the amount of work done if he is raised 12m into the air.
Answer: I belive the answer would be 720 Joules
Explanation:
Work can be calculated by multiplying an objects weight times the distance traveled. Work is measured in joules (J).
Formula: W x D = J
W= weight
D= Distance
J= joules of energy
Hope it helps
treatment for PTSD campus be described A.multumodal multi-phasic b. atheoretical C. stress inclusion D.eclectic
Answer:
Stress inclusion
Explanation:
A type of cognitive behavior therapy for PTSD is pressure inoculation preparation. CBT is a widely used form of antidepressant that can make you know wrong and/or pessimistic emotions that have influenced your actions and alter them.
I need this done by tonight!! Can anyone help me please? Answer these 4 questions
Answer:
1. 14 g of chocolate mixture.
2. 24 fl oz of chocolate milk
3. 10 cups of chocolate milk.
4. 12½ cups.
Explanation:
From the question given above, the following data were obtained:
1 TBSP = 7 g
1 Cup = 8 fl oz
2 Table spoons (TBSP) for 1 cup (8 fl oz) of milk.
1. Determination of the mass of chocolate mixture in 1 cup of chocolate milk.
From the question given above,
1 Cup required 2 Table spoons (TBSP)
But
1 TBSP = 7 g
Therefore,
2 TBSP = 2 × 7 = 14 g
Thus, 1 Cup required 14 g of chocolate mixture.
2. Determination of the number fl oz of chocolate milk in 3 cups
1 Cup = 8 fl oz
Therefore,
3 Cups = 3 × 8
3 Cups = 24 fl oz
Thus, 24 fl oz of chocolate milk are in 3 cups.
3. Determination of the number of cups of chocolate milk produce from 20 TBSP.
2 TBSP is required to produce 1 cup.
Therefore,
20 TBSP will produce = 20/2 = 10 Cups.
Thus, 10 cups of chocolate milk produce from 20 TBSP.
4. Determination of the number of cups obtained from 100 fl oz chocolate milk.
8 fl oz is required to produce 1 cup.
Therefore,
100 fl oz will produce = 100 / 8 = 12½ cups.
Thus, 12½ cups is obtained from 100 fl oz chocolate milk.
WHat does that mean?
A student asks the following question:
"If all things with mass have a gravitational field, why doesn't this glue bottle and
stapler, sitting on the counter, stick together because of gravitational forces?"
Which classmate answers correctly?
Ashton says that the gravitational fields between the bottle and the stapler
cancel out because of Newton's 3rd Law.
O Natalie says that all things with mass have a gravitational field, but the force is
very weak and cannot be perceived around small objects.
Xavier says the bottle and the stapler are way too small to have a gravitational
field.
Katherine says the bottle and the stapler have a strong gravitational field, and
would move towards each other quickly if there were no friction on the counter.
Answer:
Natalie says that all things with mass have a gravitational field, but the force is very weak and cannot be perceived around small objects.
Explanation:
The force due to gravity is proportional to the mass of the object and inversely proportional to the square of the distance between objects. The Earth is so massive that the force due to its gravity is much greater than the force between objects on the counter.
If there were no friction, the objects might move toward each other, depending on what other masses were near them tending to cause them to move in other directions.
Natalie's explanation is about the best.
__
Additional comment
The universal gravitational constant was determined by Henry Cavendish in the late 18th century using lead balls weighing 1.6 pounds and 348 pounds. His experiment was enclosed in a large wooden box to minimize outside effects. While these masses are somewhat greater than those of a glue bottle and stapler, the experiment shows the force of gravity between "small" objects can be measured.
Sultan walks for 15 km at 35° south of east.
Which of the following journeys would result in the same displacement?
Answer:
☝
Explanation:
A toy car has an initial acceleration of 2m/s^2 across a horizontal surface after it is released from rest. After the car travels for a time t consisting of only the car an open system or a closed system, and why?
a. Open system because the acceleration of the car is not constant.
b. Open system, because an external force is applied to the car that causes it to accelerate.
c. Closed system, because the speed of the car is as expected in the case where an object has uniform acceleration for a timet
d. Closed system because mechanical energy was not removed from the system as a result of a net force
Answer:
Open system, because an external force is applied to the car that causes it to accelerate.
Explanation:
In this case, the system under study is the toy car. A system may be open or closed.
An open system is acted upon by external forces but a closed system is not acted upon by any external force.
Since an external force acted on the toy car causing it to accelerate, then it is an open system.
if we ignore air resistance the mass of an object does not affect the rate at which it accelerate why?
Answer:
See explanation
Explanation:
The acceleration due to gravity on an object is independent of the mass of the object. This is so because, the acceleration due to gravity depends only on the radius of the earth and the mass of the earth.
As a result of this, all objects are accelerated to the same extent and should reach the ground at the same time when released from a height as long as other forces other than gravity are not at work.
How long ago did most Middle Eastern countries gain their independence?
A.
10-20 years ago
B.
50-100 years ago
C.
200-300 years ago
D.
400-500 years ago
Please select the best answer from the choices provided
A
B
C
D
Answer:
the correct answer is B
Explanation:
Answer:
.B
Explanation:
This is the answer on edge 2021
Have a good day!
Where do the rain forest plants get their nutrients?
from plants that fall to the forest floor
from animals that die on the forest floor
from plants and animals that die and fall to forest floor
from sunlight
Answer:
From plants and animals that die and fall to forests floor
Explanation:
Hope it helps
Mark brainliest
i believe Newton's 1st law is
Answer:
The first law states that if the net force is zero, then the velocity of the object is constant.
PLEASE HELP!!!! WILL GIVE BRAINLIEST!!! WORTH 20 PTS!!!!!
Please write the processes and tectonic plate interactions that are causing the geological event to occur. Include an explanation of convection currents.
Answer:
Explanation:
These tectonic plates rest upon the convecting mantle, which causes them to move. The movements of these plates can account for noticeable geologic events such as earthquakes, volcanic eruptions, and more subtle yet sublime events, like the building of mountains.
Answer:
Tectonic plates recurring over and over again cause a rupture in the Earth's crust. This agitates the magma in volcanoes, causing the volcano to erupt.
Explanation:
A diode for which the forward voltage drop is 0.7 V at 1.0 mA is operated at 0.5 V. What is the value of the current
Answer:
the current value is [tex]0.335 \mu A[/tex]
Explanation:
The computation of the value of the current is given below:
[tex]z_i = I_s e^{\frac{0.7}{ut} }= 10^{-3}\\\\Z_z = I_s e^{\frac{0.5}{ut} }\\\\\frac{Z_z}{Z_i}= \frac{Z_z}{10^{-3}} = e^{\frac{0.5\times 0.7}{0.025} }\\\\= 0.335 \mu A[/tex]
Hence, the current value is [tex]0.335 \mu A[/tex]
Explain whether the acceleration of the moon is higher than,less or equal to that on the earth
Answer:
If we know that [tex]m < M[/tex], then acceleration of the Moon is less to that on the Earth.
Explanation:
From Newton's Law of Gravitation we know that gravitational force between Earth and Moon ([tex]F[/tex]), measured in newtons, is expressed by this formula:
[tex]F = G\cdot \frac{M\cdot m}{r^{2}}[/tex] (1)
Where:
[tex]G[/tex] - Gravitational constant, measured in cubic meters per kilogram-square second.
[tex]M[/tex] - Mass of the Earth, measured in kilograms.
[tex]m[/tex] - Mass of the Moon, measured in kilograms.
[tex]r[/tex] - Distance between centers, measured in meters.
By comparing (1) with definition of Weight, we see that gravitational acceleration experimented by Earth ([tex]g[/tex]), measured in meters per square second, is:
[tex]g = \frac{G\cdot m}{r^{2}}[/tex] (2)
If we know that [tex]m < M[/tex], then acceleration of the Moon is less to that on the Earth.
A 65 kg box is lifted by a person pulling a rope a distance of 15 meters straight up at a constant speed. How much Power is required from the person in order to complete this task in 9 seconds?
__ Watts
Answer:
Power is 1061.67W
Explanation:
Power=force×distance/time
Power=65×9.8×15/9 assuming gravity=9.8m/s²
Power=3185/3=1061.67W
Two ice skaters stand next to each other on a frozen pond. The first skater has a mass of 65 kg and the
second skater has a mass of 82 kg. If the first skater pushes against the second with a force of 35 N, south, what are their respective
accelerations?
help me !!!
Answer:
D
Explanation:
Given that:
Mass of the first skater = 65kg
Mass of the second skater = 82kg
Force of push = 35N
Unknown:
Their respective accelerations = ?
Solution:
To solve this problem;
Force = mass x acceleration
From Newton's third law of motion, we know that action and reaction are equal and opposite.
So, the force on both Skaters is 35N
Acceleration of first Skater = [tex]\frac{35}{65}[/tex] = 0.54m/s² North
Acceleration of second Skater = [tex]\frac{35}{82}[/tex] = 0.43m/s² South