Energy can be transferred mechanically through the movement of the parts in machines, and when the motion or position of an object changes. Sound waves and seismic waves (formed during earthquakes) are mechanical waves that transfer energy through materials and from place to place.
Hope This Helps :)
An athlete runs around a circular track of radius 50 m and finishes at the same point where he began his journey. His total displacement in metre(s) is evaluated to be
Answer:
Explanation:
His displacement is 0 because he ended up exactly where he started.
Two planets are separated by a distance of 4.5x108 m. One of the planets has a mass of 2.1x1021 kg. The force of attraction between the planets is 5x1024 N. What is the mass of the other planet? (Be careful with your algebra!)
Answer:
The mass of the other planet is 7.23*10^(30) kg
Explanation:
For two objects of masses m₁ and m₂ respectively, separated by a distance r, the gravitational force between them is given by:
F = G*(m₁*m₂)/r^2
Where G = 6.67*10^(-11) m^3/(kg*s^2)
Here, we know that:
r = 4.5*10^8m
m₁ = 2.1*10^21 kg
F = 5*10^24 N
And we want to find the mass of the other planet, first, let's isolate m₂ in the force equation:
(F*r^2)/(G*m₁) = m₂
Now we can replace all the values that we know in the left side, and solve it:
m₂ =[(5*10^24 N)*( 4.5*10^8m)^2]/[6.67*10^(-11) m^3/(kg*s^2)*2.1*10^21 kg]
m₂ = 7.23*10^(30) kg
The mass of the other planet is 7.23*10^(30) kg
Richard rides a bike on a road sloping downward and inclined at an angle of 30° with the horizontal. If he moves at a constant speed of 10 meters/second, calculate his vertical downward velocity.
Answer:
[tex]v_y = 5\ m/s[/tex]
Explanation:
The vertical downward component of the speed of the bike can be simply found out by using the following geometric formula:
[tex]v_y = vSin\theta[/tex]
where,
[tex]v_y[/tex] = vertical downward component of speed = ?
v = speed = 10 m/s
θ = angle of slope = 30°
Therefore,
[tex]v_y = (10\ m/s)Sin\ 30^o\\v_y = 5\ m/s[/tex]
Unlike hard disks, which use magnetic charges to represent 1s and 0s, _____ use reflected light.
Answer:
Unlike hard disks, which use magnetic charges to represent 1s and 0s, Compact Disks, DVD's or Blue Rays use reflected light.
Explanation:
The way CD's work is that they are hit by a laser beam which is reflected on the surface of the disc. These disks have some valleys and mountains that reflect light differently so the CD player will interpret these differences in reflection as data which will then be turned into music, videos or computer files.
Un móvil recorre una trayectoria en línea recta de 6000 metros y demora 30 minutos. ¿Cuál es su rapidez expresada en Km/h?
Answer:
La rapidez del móvil es 12 kilómetros por hora.
Explanation:
Asumamos que el móvil experimenta un movimiento rectilíneo uniforme, cuya ecuación cinemática es la siguiente:
[tex]v = \frac{x}{t}[/tex] (1)
Where:
[tex]x[/tex] - Distancia recorrida, en kilómetros.
[tex]t[/tex] - Tiempo, en horas.
[tex]v[/tex] - Rapidez, en kilómetros por hora.
Si tenemos que [tex]x = 6000\,m[/tex] y [tex]t = 30\,min[/tex], entonces la rapidez del móvil es:
[tex]v = \frac{6000\,m\times \frac{1}{1000}\,\frac{km}{m}}{30\,min \times \frac{1}{60}\,\frac{h}{min} }[/tex]
[tex]v = 12\,\frac{km}{h}[/tex]
La rapidez del móvil es 12 kilómetros por hora.
what do you mean by time?
Define Circular motion and its types !
[tex] \green{\huge{\red{\boxed{\green{\mathfrak{QUESTION}}}}}} [/tex]
Define Circular motion and its types
[tex] \huge\green{\boxed{\huge\mathbb{\red A \pink{N}\purple{S} \blue{W} \orange{ER}}}}[/tex]
[tex]{ \red{ \bold {\mathbb {\textit{Circular \: motion}}}}}[/tex]
MOTION OF THE BODY CIRCULAR PATH IS CALLED CIRCULAR MOTION
A tengential is always responsible for change in speedIf the Direction of acc and velocity is same then body's speed incIf they r in oppsite direction then Body's speed dec .If speed becomes constant then tangential acc become zero .By the basis of tangial acc the circular motion is divided into two types uniform circular motion and non uniform circular motion[tex]{ \blue {\bold{UNIFORM \: CIRCULAR}}} \\ \green{ \bold{ MOTION}}[/tex]
when object in a circular path in a constant speed or constant circular speed is called uniform circular motion. In case of uniform circular motion acc tendial will be zero In case of uniform circular motion acc centripetal will be equal to net acc.[tex] { \green{ \bold{ NON UNIFORM}}} \\ {\blue{ \bold{CIRCULAR \: MOTION}}}[/tex]
Centripetal acc is not equal net acc Circular acc and tendial acc is not equal to zero .A student sects a leaf of length 7.2 cm to draw. Her drawing is 28.8 cm in length. What is the magnification of the drawing?
a) x4
b) x207.36
c) x0.25
d) x36
Answer:
A) x4
Explanation:
Magnification is equal to image size divided by the actual size, or M = I/A.
The image size is the student's drawing, which is 28.8 cm, and the actual size is 7.2 cm. Divide them, and cancel out the units, and you should get:
28.8 cm/7.2 cm = 4
The Displacement is 5m. We found that using the
Pythagorean Theorem.
Vector Quantities require both a Displacement and a
Direction.
What direction is this Vector?
South
Northeast
West
Answer:
A vector can be written as:
(R, θ)
Where R is the magnitude, in this case, we know that the magnitude of the displacement is 5m
Then:
R = 5m
and θ defines the direction, it's an angle measured from the positive x-axis.
(In the image, θ would be the angle located at the point A)
Now, if you look at the image, you can see a triangle rectangle.
Where the adjacent cathetus has a length of 4,
the opposite cathetus has a length of 3 units
the hypotenuse has a length of 5 units.
So we can use any trigonometric rule to find the value of θ, like:
sin(θ) = (opposite cathetus)/hypotenuse
Then:
sin(θ) = 3m/5m
Now we can use the inverse sin function, Asin(x), in both sides
Asin( sin(θ)) = θ = Asin( 3/5) = 36.87°
then the vector is:
(5m, 36.87°)
Now, if we define the positive y-axis as the North, and the positive x-axis as the East.
This vector would point at 36.87° North of East.
(or almost Northeast)
help helphelp it is 90km per hr
Answer:
Explanation:
The equation for acceleration is
[tex]a=\frac{v_f-v_0}{t}[/tex] which is the final velocity minus the initial velocity divided by the time. I first need to put the units all in the same terms. We have the velocity given as km/hr, but the time is given in seconds and that's not gonna work. I will change the velocity to km/sec:
[tex]90\frac{km}{hr}*\frac{1hr}{3600s}=.025\frac{km}{s}[/tex] That's the value we will use for the final velocity of this car in the equation for acceleration:
[tex]a=\frac{.025-0}{10}=.0025\frac{km}{s^2}[/tex]
The second part of this problem asks how far the car travels in this 10 seconds. We just determined that the car can travel .025 km in 1 second, so in 10 seconds the car travels 10(.025) = .25 km
Calculate the percent error of the distanc
A space shuttle was launched from the Earth to the
moon. The average, or accepted, value of the distance
of the Earth to the moon is 238,857 miles, but the
shuttle crew recorded that their trip took 226,316 miles
5.25%
07.15%
3.75%
4.45%
Answer:
5.25%
Explanation:
From the question given above, the following data were obtained:
Accepted value = 238857 miles
Measured value = 226316 miles
Percentage error =.?
Next, we shall determine the absolute error. This can be obtained as follow:
Accepted value = 238857 miles
Measured value = 226316 miles
Absolute Error =?
Absolute Error = |Measured – Accepted|
Absolute Error = |226316 – 238857|
Absolute Error = 12541
Finally, we shall determine the percentage error. This can be obtained as follow:
Accepted value = 238857 miles
Absolute Error = 12541
Percentage error =.?
Percentage error = absolute error / accepted value × 100
Percentage error
= 12541 / 238857 × 100
= 1254100 / 238857
= 5.25%
Therefore, the percentage error is 5.25%.
three condensers are connected in series across a 150 volt supply. The voltages across them are 40,50 and 60 volts respectively, and the charge on each condenser is 6×10^-8(a) calculate the capacitance of each condenser (b)calculate the effective capacitance of the combination
Explanation:
Given that,
The voltages across them are 40,50 and 60 volts respectively, and the charge on each condenser is 6×10⁻⁸ C.
(a) Capacitance of capacitor 1,
[tex]C_1=\dfrac{Q}{V_1}\\\\C_1=\dfrac{6\times 10^{-8}}{40}\\\\C_1=1.5\times 10^{-9}\ F\\\\C_1=1.5\ nF[/tex]
Capacitance of capacitor 2,
[tex]C_2=\dfrac{Q}{V_2}\\\\C_2=\dfrac{6\times 10^{-8}}{50}\\\\C_2=1.2\times 10^{-9}\ F\\\\C_2=1.2\ nF[/tex]
Capacitance of capacitor 3,
[tex]C_3=\dfrac{Q}{V_3}\\\\C_3=\dfrac{6\times 10^{-8}}{60}\\\\C_3=1\times 10^{-9}\ F\\\\C_3=1\ nF[/tex]
(b) The equivalent capacitance in series combination is :
[tex]\dfrac{1}{C}=\dfrac{1}{C_1}+\dfrac{1}{C_2}+\dfrac{1}{C_3}\\\\\dfrac{1}{C}=\dfrac{1}{1.5}+\dfrac{1}{1.2}+\dfrac{1}{1}\\\\C=0.4\ nF[/tex]
Hence, this is the required solution.
What is Unit and standard unit?
Answer:
The standard quantity with which we carry out the measurement of any physical quantity of the same kind is called a unit.
A ball of mass 0.175 kg is dropped from rest from a height of 1.25 m. It rebounds from the floor to reach a height of 0.805 m. What impulse was given to the ball by the floor
Answer:
The impulse received by the ball is - 1.561 kg.m/s
Explanation:
Given;
mass of the ball, m = 0.175 kg
initial displacement of the ball, h₁ = 1.25 m
final displacement of the ball, h₂ = 0.805 m
Assumptions:
let the downward direction of the ball be positive
let the upward direction of the ball be negative
The following equation of motion will be used to determine the final velocity of the ball at each displacement.
v² = u² ± 2gh
The final velocity of the ball when it is dropped downwards to 1.25 m;
v² = u² + 2gh
v² = 0 + 2gh
v² = 2gh
v = √2gh
v = √(2 x 9.8 x 1.25)
v = 4.95 m/s
The final velocity of the ball when it rebounds from the floor to 0.805 m;
vf² = u² - 2gh
vf² = 0² - 2gh
vf² = -2gh
vf = -√2gh
vf = - √(2 x 9.8 x 0.805)
vf = -3.97 m/s
The impulse received by the ball is calculated as;
J = ΔP = mΔv = m(vf - v)
= 0.175(-3.97 - 4.95)
= - 1.561 kg.m/s
The negative sign indicates upward direction of the impulse.
TRUE OR FALSE. when an object changed direction without changing its speed, it is not accelerating
Answer:
True.
Explanation:
The velocity vector is constant in magnitude but changing in direction. Because the speed is constant for such a motion, many students have the misconception that there is no acceleration. ... But the fact is that an accelerating object is an object that is changing its velocity.
If your weight is 588N on the earth, how far should you go from the centre of the earth so that your weight will be 300N? The radius of the earth is 6400km and the value of g on the earth surface is 9.8m/s2.
Answer:
Hmm, Well I am pretty sure the answer is 288N
Explanation:
I got the answer 288N but I am not sure if that is correct. Hope it helps! :D
Compared to the inertia of a 1-kilogram mass, the inertia of a 4-kilogram mass is
Explanation:
The inertia of a 4 kg mass is four times as great as a 1 kg mass.
A flywheel turns through 40 rev as it slows from an angular speed of 1.5 rad/s to a stop. (a) Assuming a constant angular acceleration, find the time for it to come to rest. (b) What is its angular acceleration
Answer:
The time of motion is 333.3 s
The angular acceleration is -0.0045 rad/s²
Explanation:
Given;
angular distance of the flywheel, θ = 40 rev
initial angular speed, [tex]\omega_i[/tex] = 1.5 rad/s
When the wheel comes to rest, the final angular speed, [tex]\omega_f[/tex] = 0
The angular acceleration is calculated as follows;
[tex]\omega_f^2 = \omega_i^2 + 2\alpha \theta \\\\0 = (1.5 \ rad/s)^2 + 2\alpha (40 \ rev\times \frac{2\pi \ rad}{1 \ rev} )\\\\0 = 2.25 + 160\pi \alpha\\\\160\pi \alpha = - 2.25\\\\\alpha = -\frac{2.25 }{160\pi} \\\\\alpha = -0.0045 \ rad/s^2[/tex]
The time of motion is calculated as;
[tex]\omega_f = \omega _i + \alpha t\\\\0 = 1.5 + (-0.0045t)\\\\0 = 1.5 - 0.0045t\\\\0.0045t = 1.5\\\\t = \frac{1.5}{0.0045} = 333.3 \ s[/tex]
Can somebody help me understand this
How does your ear work? 6 mark question
Answer:
It collects sound waves and channels them into the ear canal (external auditory meatus), where the sound is amplified. The sound waves then travel toward a flexible, oval membrane at the end of the ear canal called the eardrum, or tympanic membrane. Sound waves cause the eardrum to vibrate.
It collects sound waves and channels them into the ear canal (external auditory meatus), where the sound is amplified. The sound waves then travel toward a flexible, oval membrane at the end of the ear canal called the eardrum, or tympanic membrane. Sound waves cause the eardrum to vibrate. Explanation:
The Outer Ear
The auricle (pinna) is the visible portion of the outer ear. It collects sound waves and channels them into the ear canal (external auditory meatus), where the sound is amplified.
The sound waves then travel toward a flexible, oval membrane at the end of the ear canal called the eardrum, or tympanic membrane. Sound waves cause the eardrum to vibrate.
The Middle Ear
The vibrations from the eardrum set the ossicles into motion. The ossicles are actually tiny bones — the smallest in the human body. The three bones are named after their shapes: the malleus (hammer), incus (anvil) and stapes (stirrup). The ossicles further amplify the sound.
The tiny stapes bone attaches to the oval window that connects the middle ear to the inner ear. The Eustachian tube, which opens into the middle ear, is responsible for equalizing the pressure between the air outside the ear and that within the middle ear.
The Inner Ear
The sound waves enter the inner ear and then into the cochlea, a snail-shaped organ. The cochlea is filled with a fluid that moves in response to the vibrations from the oval window. As the fluid moves, 25,000 nerve endings are set into motion. These nerve endings transform the vibrations into electrical impulses that then travel along the eighth cranial nerve (auditory nerve) to the brain.
The brain then interprets these signals, and this is how we hear.
The inner ear also contains the vestibular organ that is responsible for balance.
3.00 m^3 of water is at 20.0°C.
If you raise its temperature to
60.0°C, by how much will its
volume expand?
Water
ß = 207•10-6C-1
(Unit = m^3)
Answer:
9m^3
Explanation:
Given data
volume v1= 3m^3
volume v2= ???
Temperature T1= 20.0°C.
Temperature T2= 60.0°C.
Applying the relation for temperature and volume
V1/T1= V2/T2
substitute
3/20= V2/60
3*60= V2*20
180= 20*V2
180/20= V2
V2= 9m^3
Hence the final volume is 9m^3
Put the steps of the scientific method in order
how long will it take a car to go from 0 to 45 km/hr if they are accelerating at 5 km/hr/s?
Answer:
9 seconds
Explanation:
[tex]acceleration = \frac{final \: speed - initial \: speed}{time \: taken} [/tex]
[tex]5km/ hr/ s = \frac{45 - 0 (km/ h)}{t} [/tex]
cross multiplying
[tex]5t = 45 secs \\ t = 9 \: secs[/tex]
it will take 9secs for the car to go from 0 to 45 km/ h
A shell is fired at an initial speed of 2500 m/s at an initial angle of 45 degrees. Find the shell's horizontal range and the amount of time the shell is in motion. (note that because it is fired from the ground to the ground, they displacement = 0.)
Answer:
d= 637323 meters
t= 360.5 seconds
Answer:
Explanation:
Since the height from which the shell was fired is the same as the height at which it lands (on the ground, to be specific), we will use the range equation. That is the only time you CAN use the range equation (when the initial height and the final height are exactly the same). The range equation is:
[tex]r=\frac{v_0^2sin(2\theta)}{g}[/tex] where v0 is the initial velocity, theta is the angle, and g is the pull of gravity (NOT negative). Filling in:
[tex]r=\frac{(1500)^2sin(9.0*10^1)}{9.8}[/tex] so, doing all that math gives us:
r = 6.4 × 10⁵ meters
by how much is the weight of body less on the moon surface than on earth surface why
Answer:
Our weight on moon is less than it would be on Earth.
Explanation:
Due to a difference of the strength of gravity on the moon. The moon's gravitation force is determined by the mass and the size of the moon. Since the moon has significantly less mass than the Earth, it will not pull objects toward itself at the strength that Earth will. This means that if you went to the moon you would weigh less, even though your mass stays the same.
please help with a step by step method
Answer:
Explanation:
This is a First Law of thermodynamics problem. We have to remember that the total energy available to a system is constant throughout the whole problem and that energy cannot be created or destroyed. So we need to find the total energy available right at the start. Well it just so happens that we are told that the total energy is 1000J and that it is all potential energy when the sphere is at rest and is 25 m off the ground. If the object isn't moving, all the energy is potential until it starts moving and the energy begins to convert from potential to kinetic a little bit at a time. The thing that we don't know is the mass of the shpere. Begin with the fact that the PE = 1000 (I'm going to se 2 sig fig's since there's only 1 in 1000). If
PE = 1000 and PE = mgh, then
1000 = m(9.8)(25) so
m = 4.1 kg
We also need the height at which this sphere has a PE of 600. Again, if
PE = 600 and PE = mgh, then
600 = (4.1)(9.8)h so
h = 15 Filling in the total energy equation now, using the fact that the total energy available to the system is 1000J:
TE = PE + KE and
1000 = (4.1)(9.8)(15) + [tex]\frac{1}{2}(4.1)v^2[/tex] and we are looking for v.
1000 = 6.0 × 10² + 2.1v² so
[tex]v=\sqrt{\frac{1000-6.0*10^2}{2.1} }[/tex] and
[tex]v=\sqrt{\frac{4.0*10^2}{2.1} }[/tex] gives us
v = 14 m/s
Why potential energy become equal to kinetic energy at height
Answer:
because potentil energy is redy to go but its bound up
And kinetic energy is in motion
Explanation:
Please help me with this!!!
Answer:
Its all about figuring out what numbers you times by
Explanation:
soooooooooo just x the numbers until you get it right, and i'm guessing your in a school soooo ask your teacher aswell :)
Astronomers observe the Small Magellanic Cloud (SMC), a not very dense, rather small galaxy near us. They notice that even those stars that formed recently have relatively few heavier elements (when compared to such recent stars in our Milky Way.) What is the likely explanation for this deficiency
Answer:
The reason it has few heavier elements is due to the fact that it's stars are widely spaced and this implies that it's stars have very low rate of formation and termination.
Explanation:
The Small Magellanic Cloud, is basically a very tiny galaxy located near the Milky Way. Although it's tiny, it's diameter is approximately 7,000 light-years while it also contains over hundred million stars which are widely spaced.
Now, the reason it has few heavier elements is due to the fact that it's stars are widely spaced and this implies that it's stars have very low rate of formation and termination.
As a main sequence star exhausts hydrogen in its core, its surface becomes ___ and its energy output per second (luminosity) becomes ____.
Answer:
b
Explanation:
bc
