Answer:
kinetic energy is 1/2mv^2.
which is 1/2×0.05×3^2
1/2×0.05×9.
1/2×0.45=
0.45÷2=0.225~0.23J
A space rocket accelerates uniformly from rest to 160ms^-1 upwards in 4.0s, then travels with a constant speed of 160ms^-1 for the next 5.0s.
What is the initial acceleration of the rocket?
Answer:
40 ms¯².
Explanation:
To solve this problem, we shall illustrate the question with a diagram.
The attached photo gives a better understanding of the question.
From the attached photo:
Velocity (v) = 160 ms¯¹
Time (t) = 4 secs.
Acceleration (a) =?
Acceleration (a) = Velocity (v) /time (t)
a = v/t
a = 160/4
a = 40 ms¯²
Therefore, the initial acceleration of the rocket is 40 ms¯².
Which of the following illustrates an increase in potential energy? Group of answer choices a wind-up toy winding down a person climbs a set of stairs an apple dropping from a tree a firecracker explodes
Answer:
A person climbs a set of stairs
Explanation:
Potential energy is said to be possessed by an object due to its position. As the height from the ground level increase, the potential energy increases. It is calculated by the below formula as :
P = mgh
Out of the given options, the option that illustrates an increase in potential energy is option (b) i.e. a person climbs a set of stairs. As he steps one stair, its position from ground increases. It means its potential energy increases.
A train travels southwest from point A to point B through the Arizona desert at 55 mi/h. How far will the train travel six-and-a-half hours?
Answer:
357.5 miles
Explanation:
distance = speed × time
distance = (55 mi/h) × 6.5 h = 357.5 mi
The train will travel 357.5 miles in 6.5 hours.
Dennis throws a volleyball up in the air. It reaches its maximum height 1.1\, \text s1.1s1, point, 1, start text, s, end text later. We can ignore air resistance. What was the volleyball's velocity at the moment it was tossed into the air?
Answer:
If max height = 1.1 meters, then initial velocity is 3.28 m/s
If max height is 1.1 feet, then the initial velocity is 5.93 ft/s
Explanation:
Recall the formulas for vertical motion under the acceleration of gravity;
for the vertical velocity of the object we have
[tex]v=v_0-g \,t[/tex]
for the object's vertical displacement we have
[tex]y-y_0=v_0\,t - \frac{g}{2} \,t^2[/tex]
If the maximum height reached by the object is given in meters, we use the value for g in [tex]m/s^2[/tex] which is: [tex]9.8\,\,m/s^2[/tex]
If the maximum height of the object is given in feet, we use the value for g in [tex]ft/s^2[/tex] which is : [tex]32\,\,ft/s^2[/tex]
Now, when the ball reaches its maximum height, the ball's velocity is zero, so that allows us to solve for the time (t) the process of reaching the max height takes:
[tex]v=v_0-g \,t\\0=v_0-g \,t\\g\,\,t=v_0\\t=\frac{v_0}{g}[/tex]
and now we use this to express the maximum height in the second equation we typed:
[tex]y-y_0=v_0\,t - \frac{g}{2} \,t^2\\max\,height=v_0\,(\frac{v_0}{g}) - \frac{g}{2} \,(\frac{v_0}{g})^2\\max\,height= \frac{v_0^2}{2\,g}[/tex]
Then if the max height is 1.1 meters, we use the following formula to solve for [tex]v_0[/tex]:
[tex]1.1= \frac{v_0^2}{2\,9.8}\\(9.8)\,(1.1)=v_0^2\\v_0=10.78\\v_0=\sqrt{10.78} \\v_0=3.28\,\,m/s[/tex]
If the max height is 1.1 feet, we use the following formula to solve for [tex]v_0[/tex]:
[tex]1.1= \frac{v_0^2}{2\,32}\\(32)\,(1.1)=v_0^2\\v_0=35.2\\v_0=\sqrt{35.2} \\v_0=5.93\,\,ft/s[/tex]
Answer:
11
Explanation:
for khan academy, this is the answer
A 4-N object object swings on the end of a string as a simple pendulum. At the bottom of the swing, the tension in the string is 9 N. What is the magnitude of the centripetal acceleration of the object at the bottom of the swing? Give the answer as a function of the acceleration due to gravity, g.
Answer:
Explanation:
Given mg = 4N .
m = 4 / g
At the bottom of the swing let centripetal acceleration be a
T - mg = ma
9 - 4 = ma
5 = 4 a / g
a = 5g / 4
9. An object of weight 80kg on earth is taken to a
planet where the acceleration due to the gravity is one-
third of its value on earth. The weight of the object on
the planet is
Answer:
266. 4
Explanation:
acceleration due to vravity on earth is 10m/s.
One third of it is (1/3)*10
=3.333m/s.
Weight is mass × acceleration
weight= 80kg÷ 3.333m/s
W= 266.4 Newton.
A 970-kg sports car collides into the rear end of a 2300-kg SUV stopped at a red light. The bumpers lock, the brakes are locked, and the two cars skid forward 2.9 m before stopping. The police officer, estimating the coefficient of kinetic friction between tires and road to be 0.80, calculates the speed of the sports car at impact.
Answer:
22.73 m/s or 81.72 kph
Explanation
We can find the combined mass of both cars as
970 kg + 2300 kg = 3270 kg.
Then the normal force of the cars can be calculated as
F(n)= mg
Where g is acceleration due to gravity 9.8m/s^2
3270 kg ×9.8 = 32046 kg*m/s^2.
coefficient of kinetic friction between tires and road to be 0.80 × F(n)
Then the frictional force can be calculated as
= (32046kg*m/s^2 × 0.80 )
= 25636.8 kg*m/s^2
We can now calculate the work done that was used stopping the cars as
Frictional force × distance
(25636.8 kg*m/s^2 ) × 2.9m= 74346.72kg*m^2/s^2
From kinetic energy formula, the combined velocity of the car can be determined
E=0.5 M V²
√(2E/M) = V
√(2*74346.72kg*m^2/s^2 / 3270 kg) = V
V= √ (45.472)
V=6.743293m/s
the momentum of both cars can be determined as
6.743293m/s * 3270 kg
= 22050.57kg*m/s
Now the final momentum of both cars must be equal to the the momentum of
the sports car just prior to the collision. Therefore, the speed of the sports car at impact.
=(22050.57 kg*m/s) / 970 kg = 22.73 m/s
We can convert that to km/h.
22.73 m/s * 3600 s/h / 1000 m/km = 81.72 kph
An emf of 22.0 mV is induced in a 519-turn coil when the current is changing at the rate of 10.0 A/s. What is the magnetic flux through each turn of the coil at an instant when the current is 3.70 A?
Answer:
[tex]\phi=1.56\times 10^{-5}\ Wb[/tex]
Explanation:
Given that,
Emf, V = 22 mV
Number of turns in the coil us 519
Rate of change of current is 10 A/s.
We need to find the magnetic flux through each turn of the coil at an instant when the current is 3.70 A.
Let's find the inductance first. So,
[tex]L=\dfrac{\epsilon}{(dI/dt)}\\\\L=\dfrac{0.022}{10}\\\\L=0.0022\ H[/tex]
We have,
[tex]L=\dfrac{N\phi}{I}[/tex], [tex]\phi[/tex] is magnetic flux
[tex]\phi=\dfrac{LI}{N}\\\\\phi=\dfrac{0.0022\times3.7}{519}\\\\\phi=1.56\times 10^{-5}\ Wb[/tex]
So, the magnetic flux is [tex]1.56\times 10^{-5}\ Wb[/tex].
A 30-µF capacitor is charged to an unknown potential V and then connected across an initially uncharged 10-uF capacitor. If the final potential difference across the .10-µF capacitor is 20 V, determine V
Answer:
V = 26.6 volts
Explanation:
Let Initial Potential Difference be V.
Charge (Q) accumulated in 30 mF Capacitor =
Q = C * V
Q= 30 * V
Now, Common Potential after connecting to uncharged 10mF capacitor in parallel = 20 Volt
Total Charge =Total Capacity * Common Potential
30 * V = ( 30 + 10) * 20
V = 26.6 volts
The unknown potential across the 30-µF capacitor is 6.67 V.
The given parameters;
initial capacitance of the capacitor, C = 30 µFunknown potential in the 30 µF capacitor = V₁potential difference in 10 µF capacitor = 20 VSince the potential difference between the two capacitors are different, the two capacitors are in series connection.
In series circuit arrangement, the quantity of charge flowing in each capacitor is the same.
[tex]Q_{30\ \mu F} = Q_{10 \ \mu F}[/tex]
[tex]Q_{10 \ \mu F} = CV = 10\times 10^{-6} \times 20 = 0.0002 \ C[/tex]
The potential difference are different and the total potential is given as;
[tex]V_{T} = V_1 + V_2\\\\V_1 = \frac{Q}{C_1} \\\\V_2 = \frac{Q}{C_2} \\\\V_1+V_2 = \frac{Q}{C_1} + \frac{Q}{C_2}\\\\V_1 + V_2 = Q(\frac{1}{C_1} + \frac{1}{C_2} )\\\\V_1 + 20 = Q(\frac{1}{C_1} + \frac{1}{C_2} )\\\\V_1+ 20 = \frac{Q(C_2+ C_1)}{C_1 C_2} \\\\V_1 = \frac{Q(C_2+ C_1)}{C_1 C_2} - 20[/tex]
[tex]V_1 = \frac{0.0002(10\times 10^{-6}\ + \ 30\times 10^{-6})}{(30\times 10^{-6}) (10\times 10^{-6})} - 20\\\\V_1 = \frac{8\times 10^{-9}}{3\times 10^{-10}} - 20\\\\V_1 = 26.67 - 20\\\\V_1 = 6.67 \ V[/tex]
Thus, the unknown potential across the 30-µF capacitor is 6.67 V.
Learn more here:https://brainly.com/question/23899758
Sound waves move the fastest through which medium?
Answer:
Sound travels fastest through solids.
Explanation:
This is because molecules in a solid medium are much closer together than those in a liquid or gas, allowing sound waves to travel more quickly through it. In fact, sound waves travel over 17 times faster through steel than through air.
Sound waves move the fastest through the solid. The speed of the sound wave in the liquid and gas is low,
What is sound wave?A sound wave is produced when a medium begins to vibrate. When an entity vibrates, a pressure wave is formed, which causes sound.
Solids transmit sound the fastest. Because the molecules in a solid medium are much closer together than in a liquid or gas, sound waves can move through it much faster.
Hence, sound waves move the fastest through the solid.
To learn more about the sound wave, refer to the link;
https://brainly.com/question/11797560
#SPJ2
A force of 20N changes the position of a body. If mass of the body is 2kg, find the acceleration produced in the body.2. A ball of mass 500g is thrown upwards with a velocity of 15m/s. Calculate its momentum at the highest point.
Explanation:
Hello there!!!
You just need to use simple formula for force and momentum,
F= m.a
and momentum (p)= m.v
where m= mass
v= velocity.
a= acceleration .
And the solutions are in pictures.
Hope it helps..
A series combination of 12 Ω and 3 Ω is connected in parallel with another series combination of 6 Ω and 3 Ω. If a potential difference of 4 V is applied across it find the i) current is drawn from the battery ii) current through 12 Ω resistor (iii)potential difference across 6 Ω resistor?
Answer:
a) 0.73A
b) 0.23A
c) 2.76V
Explanation:
We need to first resolve the two resistors in series. The resistors in series are
12 Ω and 3 Ω AND 6 Ω and 3 Ω
For 12 Ω and 3 Ω in series, total effective resistance = 12 Ω + 3 Ω = 15 Ω
For 6 Ω and 3 Ω in series, total effective resistance = 6 Ω + 3 Ω = 9 Ω
Since the equivalent series resistors i.e 15Ω ND 9Ω are connected in parallel, the total effective resistance Rt will be expressed as;
1/Rt = 1/15+1/9
1/Rt = (3+5)/45
1/Rt = 8/45
Rt = 45/8 Ω
a) If a potential difference of 4 V is applied across it, the total current I in the circuit can be derives using the ohms law.
According to the law E = IRt
Given E = 4V, Rt = 45/8
I = E/Rt
I = 4/(45/8)
I = 4 * 8/45
I = 32/45
I = 0.73A
Hence, the current drawn from the battery is 0.73A
b) Before we can calculate the current in the 12Ω resistor, we need to calculate the current in the equivalent resistance of 15Ω(sum of 12Ω and 3Ω)
Current in the 15Ω resistor = Voltage across the 15Ω resistor/Resistance
Current in the 15Ω resistor = 4/15
Current in the 15Ω resistor = 0.27A
Since the same current flows in a series connected resistors, hence the correct in the 12ohms resistor is also 0.27A.
c) Before we can calculate the pd across the 6ohms resistor, we need to know the voltage across the effective resistance of 9ohms(6ohms+3ohms). The pd across the 9ohm resistance will be the same as the source voltage i.e 4Volts.
We will need to share this 4volts between the 6ohms and the 3ohms using ohms law.
According to the law, V = IR
For the 6ohms resistor, voltage across it will be;
V = (0.73-0.27)×6
V= 0.46×6
V = 2.76Volts.
Hence the voltage across the 6ohms resistor is 2.76V.
Which atomic number corresponds to the element which is most stable?
01
03
28
36
Answer:
Which atomic number corresponds to the element which is most stable?
01
03
28
36
36 is your answer.
A ship sets out to sail to a point 123 km due north. An unexpected storm blows the ship to a point 112 km due east of its starting point. (a) How far and (b) in what direction (as an angle from due east, where north of east is a positive angle) must it now sail to reach its original destination
Answer:
Explanation:
We shall represent the point of destination and point of new starting point in vector form .
i and j will represent east and north .
point of destination = 123 j
starting point = 112 i
distance between the two
D = 123 j - 112 i
magnitude of D = √ ( 123² + 112² )
= 166.35 km
Direction of D
Tanθ = - 123 / 112
= - 1.09
θ = 132.54 degree from east in positive angle .
How has the games changed over the years?
Answer:
The definition of the particular circumstance consists provided in the subsection on the interpretation elsewhere here.
Explanation:
Throughout the past 10-20 years, the computer games industry is experiencing some insane shifts. Several of the adjustments are responsible for the observed market developments, while others are related to just the tech boom as well as technological development across the global economy. Here is another glimpse at some instances of how and why the gaming industry has evolved in just the last few decades.A foot is 12 inches and a mile is 5280 ft, exactly. A centimeter is exactly 0.01m or mm. Sammy is 5 feet and 5.3 inches tall. What is Sammy's Height in inches?
The answer is 65.3 inches tall
Explanation:
To know the heigh of Sammy in inches it is necessary to convert the 5 feet to inches and add this number to 5.3 inches as the statement mentions "Sammy is 5 feet and 5.3 inches tall". Additionally, it is known each foot is equal to 12 inches ( 1 foot = 12 inches). According to this, the simplest method to convert feet to inches is to multiply the feet given by 12. The process is shown below:
1 foot = 12 inches
feet to inches = number of feet x 12
5 feet x 12 = 60 inches
This means 5 feet is equal to 60 inches. Now, 60 inches + 5.3 inches = 65.3 inches (total height of Sammy in inches)
please help ASAP.
these are examination questions ..
no nonsense answers .
i will mark as brainliest if you got it correct .
Answer:
1st question c part
2nd question c part
Answer answer answer it it it
Answer:
(B) Parachutes
Explanation:
Air resistance works to slow down trains and airplanes, so it isn't desirable. Air resistance also causes pendulums to slow and stop.
Parachutes need air resistance to slow a person's fall. So air resistance is desirable here.
Answer:
B i answered it it it
Explanation:
Match the following:
Tailored software
. Utility software
Operating system
Software
Packaged software
Set of programs
Library management system
Scan viruses
Microsoft Office
used to coordinate the hardw
the computer
Answer:
1) Tailored software Library management system
2) Utility software Scan viruses
3) Operating system Used to coordinate the hardware of the computer
4) Packaged software set of programs Microsoft office
Explanation:
1) A tailored software, also known as a custom software, is one that is designed and tailor-made only for a particular organisation
2) A utility software is a computer maintenance and analysis software used to enable proper functioning of the computer by performing restorative and maintenance tasks
3) Operating system software
The operating system software controls the operation of the computer hardware within the system and enables the operation of other programs in the computer
4) Packaged software are a collection of programs that are oriented to perform interrelated tasks that a focused to a particular area, such as Microsoft Office.
famous comparative and superlative form
Answer:
comparative----more famous, superlative----- most famous
[tex]\huge{\fbox{\red{Answer:}}}[/tex]
Word Given :Famous
___________________✍
Comparative Form : more famous
Superlative Form : most famous
Hope you understand❣
The model of the atom has changed as scientists have gathered new evidence. Four models of the atom are shown below, but one important model is missing. An image at left with overlapping red and blue balls in the center with a circular fuzzy green cloud outside them. An image at center left with a purple ball in the center surrounded by overlapping concentric black ovals, each with a small green ball on each of the 6 ovals. An image at center right with a large black cross in a purple circle with a black line around the purple, with 10 small green balls dispersed within the purple circle. An image at right with a purple center outlined in black with two concentric black circles around the center, the inner circle having 2 small green balls on it and the outer circle having 8 small green balls on it. Which atomic model is missing from this set? Bohr’s model Dalton’s model Rutherford’s model Thomson’s model
Answer:
Thomson’s model
Explanation:
Thompson regarded the atom largely as a sphere of positively charged matter in which negative charges were embedded.
This came to be known as the plum pudding model of the atom because it resembles a pudding studded with currants.
This was an early model of the atom and did not survive further experimental scrutiny of the structure of the atom.
Answer:
Thompsons model
Explanation:
i got it right on the quiz
A 30-cm long string, with one end clamped and the other free to move transversely, is vibrating in its second harmonic. The wavelength of the constituent traveling waves is:
Answer:
[tex]\lambda[/tex] = 40 cm
Explanation:
given data
string length = 30 cm
solution
we take here equation of length that is
L = [tex]n \times \frac{1}{4} \lambda[/tex] ...............1
so
total length will be here
[tex]L = \frac{\lambda}{2} + \frac{\lambda}{4}\\[/tex]
[tex]L = \frac{3 \lambda }{4}[/tex]
so [tex]\lambda[/tex] will be
[tex]\lambda = \frac{4L}{3}\\\lambda = \frac{4\times 30}{3}[/tex]
[tex]\lambda[/tex] = 40 cm
You are hiking in a canyon and you notice an echo. You decide to let out a yell and notice it took 2 seconds before you heard the echo of your yell. How far away is the canyon wall that reflected your yell
Answer:
d = 343 m
Explanation:
Given that,
You notice that an echo took 2 seconds before you heard the echo of your yell.
We need to find that how far away is the canyon wall that reflected your yell. It means we need to find the distance.
The distance covered by an object is given by :
d = v × t
v is speed of sound in air, v = 343 m/s
The sound took 1 s to reach the wall and 1 s back to you.
It means that,
d = 343 × 1
d = 343 m
So, canyon will reflect your yell at a distance of 343 m
A body with an initial velocity of 10m/s has an acceleration of 8m/s^2. Determine graphically the velocity after 5 seconds, & the distance travelled in that time. Verify your answer using the equations of motion.
Answer:
From the graph, at t = 5 seconds, the velocity = 50 m/s as shown also in the above table
Please find attached the graph
Explanation:
The initial velocity of the body = m/s
The acceleration of the body = 8 m/s²
The velocity after 5 seconds can be determined graphically and by calculation as follows;
Graphically, we have the data points which can be found by the straight line relation v = u + a×t,
Where ,
a = The slope = 8 m/s²
u = 10 m/s = The y-intercept
Which gives;
v = 10 + 8 × t
The following data can be calculated for various time t;
Time, t Velocity , v
0, 10
1, 18
2, 26
3, 34
4, 42
5, 50
6, 58
From the graph, at t = 5 seconds, the velocity = 50 m/s as shown also in the above table
Please find attached the graph
By calculation, we have;
v = u + a×t
Where;
v = The final velocity
u = The initial velocity = 10 m/s
a = The acceleration = 8 m/s²
t = The time = 5 seconds
v = 10 + 5× 8 = 50 m/s.
If an object floats, the volume of the displaced water is equal to the volume of the whole object. True or false?
Answer:
True
Explanation:
This is in fact what the Archimedes principle states, and what he used in the famous anecdote about finding if the crown of the King was really made of gold.
The length and breadth of rectangular sheet of metal are 4.234m, 1.005,
and 2.01cm respectively.
Give the area and volume of sheet to correct significant figures..
Answer:
The area of the sheet of metal = 4.255 m²
The volume of the sheet of metal = 0.08553 m³
Explanation:
The area of a rectangle is given by the following relation;
Area, A = Length × Breadth
Therefore, the area of the rectangular sheet of metal, A[tex]_m[/tex], is given as follows;
A[tex]_m[/tex] = 4.234 m × 1.005 m = 4.255 m²
The area of the sheet of metal = 4.255 m²
The volume of the metal sheet id given by the relation, volume V[tex]_m[/tex]= area × Thickness
The thickness of the sheet of metal = 2.01 cm = 0.0201 m
Therefore,
V[tex]_m[/tex] = 4.255 m × 0.0201 m = 0.08553 m³
The volume of the sheet of metal = 0.08553 m³.
Answer:
Are yarr mei bhi Indian hu.....
Explanation:
Tumse milkar accha laga
with solutions please give with solution
if u give me with solution I will mark in brainlist
Answer:
Magnitude of Force : 0.8 N
Explanation:
We know that the velocity of this particle changes from 15ms⁻¹, or in other words 15m / s, to the respective velocity 25m / s over the course of 2.5 seconds. Given this information we can determine the acceleration of the particle,
a = v₁ - v₂ / t = 25 - 15 / 2.5 = 10 / 2.5 = 4m / s²
Knowing the acceleration we can calculate the magnitude of the force using the formula f = ma - Newton's second law of motion,
f = m [tex]*[/tex] a = 200g [tex]*[/tex] 4m / s² = 800 g [tex]*[/tex] m / s²
Remember however that Newtons are in the standard units kg [tex]*[/tex] m / s². Therefore we have to convert 800 g to kg to receive our solution,
800 g = 800 / 1000 kg = 0.8 kg,
Magnitude of Force = 0.8 N ; Solution = Option B
Explain.
4. State the limitations of our senses to obtain accurate in
formation concerning
our environment.
Answer:
The limits of our senses are
Limits of Sight
Our vision field of view is 120° sideways and 135° vertically
Angular visual resolution is about an 1/60 of one degree
The presence of blind spots in the eyes
Limits of sound
The hearing range is within 20 - 20,000 Hz and our threshold hearing above 0 to 5 decibel of sound
Limits of taste
We have very limited sense of taste which is partly dependent on our sense of smell with little objectivity in distinguishing tastes
Sense of smell
The establishing of the effectiveness of human sense of smell is gauged on numerous parameters with certain tests being inconsistent, as such, it is difficult to clearly establish the effectiveness of the human sense of smell
In comparison with the sense of smell of other living things such as dogs, the human sense organ is comparatively low
Explanation:
An iron ball at 40°C is dropped in a mug containing water at 40°C.
The heat will
(a) flow from iron ball to water.
(b)
not flow from iron ball to water or from water to iron ball
(c)
flow from water to iron ball
(d) increase the temperature of both
10. A wooden spoon is dipped in a cup of ice cream. Its other end
(a) becomes cold by the process of conduction.
(b) becomes cold by the process of convection
(c) becomes cold by the process of radiation.
(d) does not become cold.
Answer:
1. option a
2. option d
Explanation:
HOPE IT HELPS YOU
prove p=f/a science chapter pressure
Explanation:
Let 'F' be force acting perpendicularly, 'A' be the area and 'P' be the pressure exerted.
Then,
Pressure is directly proportional to the the force acting perpendicularly i.e.
P ∝ F ............. (i)
Pressure is inversely proportional to the area on which force acts i.e.
P ∝ 1/A ........... (ii)
Combining equations (i) and (ii),
P ∝ F/A
or, P = K × F/A [where K is a constant]
If F is 1N, A is 1m² and P is 1 N/m², then K is 1.
So, P = F/A proved...
