Help me with this review question please.
Answer:
K E=( mv²)/2
=(60×3.5²)/2
=367.5J
Predicted height and total energy
Answer:
The predicted height is 2.809 meters, writing this in centimeters we get (1m = 100cm):
h = 2.809 m = (2.809)*(100cm) = 280.9 cm
And the total energy is:
E = 6.696 J
Explanation:
First let's see the problem.
We have an object of mass m = 274g which is thrown upwards with an initial velocity v0 = 6.991 m/s, in a place with a gravitational acceleration of g = 8.7 m/s^2
When the object is on the air, the only force acting on it will be the gravitational force, then the acceleration of the object will be equal to the gravitational acceleration, then we can write:
a(t) = -8.7 m/s^2
Where the negative sign is because this acceleration points down.
Now to get the velocity of the object we can integrate over time to get:
v(t) = (-8.7 m/s^2)*t + v0
Where v0 is a constant of integration, which is the initial velocity, then we can write this as:
v(t) = (-8.7 m/s^2)*t + 6.991 m/s
Now we can integrate again over the time to get the position equation.
p(t) = (1/2)*(-8.7 m/s^2)*t^2 + (6.991 m/s)*t + p0
Where p0 is the initial position, because the ball is being thrown from the ground, the initial position is 0.
Then the position equation is:
p(t) = (1/2)*(-8.7 m/s^2)*t^2 + (6.991 m/s)*t
Ok, now we know all the movement equations for the object.
The first thing we want to know is the maximum height of the object.
We know that the object reaches its maximum height when the velocity is zero (this is, the velocity stops being positive, meaning that the object stops going up, then in that time we have the maximum height)
We need to solve:
v(t) = 0m/s = (-8.7 m/s^2)*t + 6.991 m/s
(8.7 m/s^2)*t = 6.991 m/s
t = 6.991 m/s/( (8.7 m/s^2) = 0.804 seconds
The maximum height of the object is given by:
p(0.804s) = (1/2)*(-8.7 m/s^2)*(0.804)^2 + (6.991 m/s)*(0.804) = 2.809 m
The maximum height of the object is 2.809 meters.
Now let's find the maximum energy.
Remember that the energy of an object can be written as the sum of the potential energy U and the kinetic energy K.
E = K + U
Such that for an object of mass m and velocity v, the kinetic energy is:
K = (1/2)*m*v^2
And for an object of mass m, at a height h from the ground and with gravitational acceleration g, the potential energy is:
U = m*g*h
Now, when the object is at its maximum height, the velocity is zero.
Then K = 0
And for conservation of energy, the total energy of the object becomes potential energy.
E = 0 + U
E = U
So if we find the potential energy at the maximum height of the object's path, we can find the total energy of the object.
We know that:
mass = m = 274g = 0.274 kg (here i used that 1kg = 1000g)
height = h = 2.809 meters.
gravitational acceleration = g = 8.7 m/s^2
Then the potential energy at this point is:
U = 0.274 kg*(2.809 meters)*(8.7 m/s^2) = 6.696 J
This means that the total energy of the object is:
E = 6.696 J
Please solve for 15 points. Please don’t input a link.
Answer:
a). Single replacement.
Explanation:
Because one element replaces another element in a compound
A substance whose shape can easily change is a
a glass rod is given a positive charge by rubbing it with silk. how did the rod become positive ?
Answer:
When the glass rod is rubbed with silk, the silk strips electrons from the rod, leaving it a positive charge. When the hard rubber rod is rubbed with wool, it gains electrons from the wool, gaining a negative charge.
Explanation:
one negative change you may encounter as a student or an employee
Answer:
you may get bullied or teased for being a differrent race, ethnic.
Answer:
Workload
Explanation:
You may feel stressed about a heavier workload or more too do. You will also be paid as an employee unlike, a student.
Two identical copper blocks are connected by a weightless, unstretchable cord through a frictionless pulley at the top of a thin wedge. One edge of the wedge is vertical, and the tip makes an angle of 33. The block that hangs vertically weighs 2.85 kg, and the block on the incline weighs 2.94 kg. If the two blocks do not move, what is magnitude of the force of friction on the second second block
Answer:
13.6 N
Explanation:
Since one side of the wedge is vertical and the wedge makes and angle of 33 with the horizontal, the angle between the weight of the copper block on the incline and the incline is thus 90 - 33 = 57.
Let M be the mass of the block that hangs, m be the mass of the block on the incline and T be the tension in the weightless unstretchable cord.
We assume the motion is downwards in the direction of the hanging block, M.
We now write equations of motion for each block.
So
Mg - T = Ma (1) and T - mgcos57 - F = ma where F is the frictional force on the block on the incline and a is their acceleration.
Now, since both blocks do not move, a = 0.
So, Mg - T = M(0) = 0 and T - mgcos57 - F = m(0) = 0
Mg - T = 0 (3) and T - mgcos57 - F = 0 (4)
From (3), T = Mg
Substituting T into (4), we have
T - mgcos57 - F = 0
Mg - mgcos57 - F = 0
So, Mg - mgcos57 = F
F = Mg - mgcos57
F = (M - mcos57)g
Since g = acceleration due to gravity = 9.8 m/s², and M = 2.94 kg and m = 2.85 kg.
We find F, thus
F = (2.94 kg - 2.85 kgcos57)9.8 m/s²
F = (2.94 kg - 2.85 kg × 0.5446)9.8 m/s²
F = (2.94 kg - 1.552 kg)9.8 m/s²
F = (1.388 kg)9.8 m/s²
F = 13.6024 kgm/s²
F ≅ 13.6 N
Please help me please with both questions
Answer:
6 - iron
7 - by stringing many magnets together
Explanation:
6 - substances such as iron, cobalt, and nickel, most of the electrons spin in the same direction. This makes the atoms in these substances strongly magnetic—but they are not yet magnets. ... The piece of iron has become a magnet. Some substances can be magnetized by an electric current.
7 - it is that only
If each Coulomb of charge is given 20 Joules of energy, what is the voltage of the battery?
A. 20 V
B. 5 V
C. 10 V
D. Not enough info
Answer:
Explanation:
V = J/C
V = 20/1
= 20 v
Option A is the correct answer
What causes the Coriolis effect?
A
The sun's position relative to Earth
B.
Earth's orbit around the sun
с
Moon phases
D
Earth's rotation
The energy goes from _____ to the _____ above it.
Answer:
The energy goes from the ground state to the excited states above it.
Which nucleus completes the following equation?
Answer:
Option D. ²³⁹₉₃Np
Explanation:
From the question given above, the following data were:
²³⁹₉₂U —> ⁰₋₁e + __
Let ⁿₘX represent the unknown. Thus, the equation above becomes
²³⁹₉₂U —> ⁰₋₁e + ⁿₘX
Next, we shall determine n, m and X. This can be obtained as follow:
239 = 0 + n
239 = n
n = 239
92 = –1 + m
Collect like terms
92 + 1 = m
93 = m
m = 93
ⁿₘX => ²³⁹₉₃X => ²³⁹₉₃Np
Thus, the balanced equation becomes:
²³⁹₉₂U —> ⁰₋₁e + ⁿₘX
²³⁹₉₂U —> ⁰₋₁e + ²³⁹₉₃Np
Option D gives the correct answer to the question.
Answer:
D
Explanation:
239 93 Np
Which of the following could be an example of chemical weathering?
a. rocks tumbling against each other
b. water seeping into the ground, dissolving the limestone to form a cave
c. a waterfall boring out a whole in a rock under it
Answer: B
Explanation:
Answers A and C are examples of physical weathering while B is chemical weathering when water and lime mix it creates a reaction
Which of the following best describes wind?
A А
Sinking warm air moving a few feet above the ground
B
An air current formed by changes in ocean tides
с
Cool air rushing in to fill an area of low pressure
D
Rising warm air pushing cool air down toward Earth
The correct statement about the wind is:
Cool air rushing in to fill an area of low pressureWhat is the wind?Wind is the movement of air currents in relation to the Earth's surface, which is caused by pressure differences and air movement.
Characteristics of the windIt is a meteorological phenomenon originated in the movements of rotation and translation of the Earth.When the rising air cools and loses the moisture it was carrying, due to condensation and rain, the result is dry and cool air.Therefore, we can conclude that the wind is the current of air that occurs in the atmosphere due to natural causes, from high pressure areas to low pressure areas.
Learn more about Characteristics of the wind here: https://brainly.com/question/11463167
Two protons (each with q = 1.60 x 10-19)
in a nucleus are located 1.00 x 10-15 m
apart. How much electric force do they
exert on each other?
[?] N.
Answer:
230.4 N
Explanation:
From the question given above, the following data were obtained:
Charge (q) of each protons = 1.6×10¯¹⁹ C
Distance apart (r) = 1×10¯¹⁵ m
Force (F) =?
NOTE: Electric constant (K) = 9×10⁹ Nm²/C²
The force exerted can be obtained as follow:
F = Kq₁q₂ / r²
F = 9×10⁹ × (1.6×10¯¹⁹)² / (1×10¯¹⁵)²
F = 9×10⁹ × 2.56×10¯³⁸ / 1×10¯³⁰
F = 2.304×10¯²⁸ / 1×10¯³⁰
F = 230.4 N
Therefore, the force exerted is 230.4 N
Answer:
230.4
Explanation:
acellus
A solenoid of 2100 turns, area 10 cm2, and length 30 cm carries a current of 4.0 A. (a) Calculate the magnetic energy stored in the solenoid from 1/2 LI 2. J [2 points] 0 attempt(s) made (maximum allowed for credit
Answer:
E = 0.1472 J
Explanation:
Given that,
The number of turns in the solenoid, N = 2100
Area of the solenoid, A = 10 cm² = 0.001 m²
The length of the solenoid, l = 30 cm = 0.3 m
Current in the solenoid, I = 4 A
We need to find the magnetic energy stored in the solenoid. The expression for the stored energy is :
[tex]E=\dfrac{1}{2}LI^2[/tex]
Where
L is self inductance of the solenoid,
[tex]L=\dfrac{\mu_oN^2A}{l}\\\\L=\dfrac{4\pi \times 10^{-7}\times 2100^2\times 0.001}{0.3}\\\\L=0.0184\ H[/tex]
So,
[tex]E=\dfrac{1}{2}\times 0.0184\times 4^2\\\\E=0.1472\ J[/tex]
So, 0.1472 J of energy is stored in the solenoid.
A mass MM uniform solid cylinder of radius RR and a mass MM thin uniform spherical shell of radius RR roll without slipping. If both objects have the same kinetic energy, what is the ratio of the speed of the cylinder to the speed of the spherical shell
Answer:
vcyl / vsph = 1.05
Explanation:
The kinetic energy of a rolling object can be expressed as the sum of a translational kinetic energy plus a rotational kinetic energy.The traslational part can be written as follows:[tex]K_{trans} = \frac{1}{2}* M* v_{cm} ^{2} (1)[/tex]
The rotational part can be expressed as follows:[tex]K_{rot} = \frac{1}{2}* I* \omega ^{2} (2)[/tex]
where I = moment of Inertia regarding the axis of rotation.ω = angular speed of the rotating object.If the object has a radius R, and it rolls without slipping, there is a fixed relationship between the linear and angular speed, as follows:[tex]v = \omega * R (3)[/tex]
For a solid cylinder, I = M*R²/2 (4)Replacing (3) and (4) in (2), we get:[tex]K_{rot} = \frac{1}{2}* \frac{1}{2} M*R^{2} * \frac{v_{cmc} ^{2}}{R^{2}} = \frac{1}{4}* M* v_{cmc}^{2} (5)[/tex]
Adding (5) and (1), we get the total kinetic energy for the solid cylinder, as follows:[tex]K_{cyl} = \frac{1}{2}* M* v_{cmc} ^{2} +\frac{1}{4}* M* v_{cmc}^{2} = \frac{3}{4}* M* v_{cmc} ^{2} (6)[/tex]
Repeating the same steps for the spherical shell:[tex]I_{sph} = \frac{2}{3} * M* R^{2} (7)[/tex]
[tex]K_{rot} = \frac{1}{2}* \frac{2}{3} M*R^{2} * \frac{v_{cms} ^{2}}{R^{2}} = \frac{1}{3}* M* v_{cms}^{2} (8)[/tex]
[tex]K_{sph} = \frac{1}{2}* M* v_{cms} ^{2} +\frac{1}{3}* M* v_{cms}^{2} = \frac{5}{6}* M* v_{cms} ^{2} (9)[/tex]
Since we know that both masses are equal each other, we can simplify (6) and (9), cancelling both masses out.And since we also know that both objects have the same kinetic energy, this means that (6) are (9) are equal each other.Rearranging, and taking square roots on both sides, we get:[tex]\frac{v_{cmc}}{v_{cms}} =\sqrt{\frac{10}{9} } = 1.05 (10)[/tex]
This means that the solid cylinder is 5% faster than the spherical shell, which is due to the larger moment of inertia for the shell.The photograph shows part of the Great Plains of North America. How do
plains form?
A. Magma rises at a divergent plate boundary.
B. Tectonic movements make folds and faults in the crust.
C. Continental plates slip past each other at a transform boundary.
D. Water, wind, or glaciers either remove or deposit crust.
SUBMIT
2 PREVIOUS
Answer:
Some plains form as ice and water erodes, or wears away, the dirt and rock on higher land. Water and ice carry the bits of dirt, rock, and other material, called sediment, down hillsides to be deposited elsewhere. As layer upon layer of this sediment is laid down, plains form. Volcanic activity can also form plains.
a disk of radius 10 cm speeds up from rest. it turns 60 radians reaching an angular velocity of 15 rad/s. what was the angular acceleration?
b. how long did it take the disk to reach this velocity?
Answer:
a) The angular acceleration is 1.875 radians per square second.
b) The time taken by the disk to reach the final angular speed is 8 seconds.
Explanation:
a) Let suppose that the disk accelerates uniformly, given that initial and final angular speed ([tex]\omega_{o}[/tex], [tex]\omega_{f}[/tex]), in radians per second, and change in angular position ([tex]\Delta \theta[/tex]), in radians, are known. The angular acceleration ([tex]\alpha[/tex]), in radians per square second, are found by using this expression:
[tex]\alpha = \frac{\omega_{f}^{2}-\omega_{o}^{2}}{2\cdot \Delta \theta}[/tex] (1)
If we know that [tex]\omega_{o} = 0\,\frac{rad}{s}[/tex], [tex]\omega_{f} = 15\,\frac{rad}{s}[/tex] and [tex]\Delta \theta = 60\,rad[/tex], then the angular acceleration of the disk is:
[tex]\alpha = \frac{\omega_{f}^{2}-\omega_{o}^{2}}{2\cdot \Delta \theta}[/tex]
[tex]\alpha = 1.875\,\frac{rad}{s^{2}}[/tex]
The angular acceleration is 1.875 radians per square second.
b) The time taken by the disk to reach the final angular velocity is determined by the following kinematic formula:
[tex]t = \frac{\omega_{f}-\omega_{o}}{\alpha}[/tex] (2)
Where [tex]t[/tex] is the time, in seconds.
If we know that [tex]\omega_{o} = 0\,\frac{rad}{s}[/tex], [tex]\omega_{f} = 15\,\frac{rad}{s}[/tex] and [tex]\alpha = 1.875\,\frac{rad}{s^{2}}[/tex], then the time taken by the disk is:
[tex]t = \frac{\omega_{f}-\omega_{o}}{\alpha}[/tex]
[tex]t = 8\,s[/tex]
The time taken by the disk to reach the final angular speed is 8 seconds.
I beg you plz help me asap!!!
Q. How does new planet change our understanding about the universe?
Answer:
a.
Explanation:
there would be a new planet is our solar system which could cause different gravitation pull on all the planets also there could be possible be new life form or other valuable metals that haven't been discovered on this planet. hope this helps somewhat
An airplane flies 1000 miles in 2 hours. What is its average speed in miles per hour?
Answer:
500km per hour
Explanation:
if in 2 hours the airplane flies 1000 km then 1000 divided by 2 is 500km per hour.
An enormous thunderstorm covers Dallas-Ft. Worth. Your best friend Clark is a storm chaser and heads to the center of the storm to take some readings while you stay dry at home. While Clark is at the center of the storm, he sees and hears lightning strike a tree that is 150 m from where he is standing. You are 127 km from the tree. How long does it take for the sound to reach Clark
Answer:
t = 0.437 s
Explanation:
The speed of sound is a constant that is worth v = 343 m / s
v = d / t
t = d / v
the time it takes for the sound to reach Clark at d = 150 m is
t = 150/343
t = 0.437 s
This same sound takes much longer to reach you
t₂ = 127 10³/343
t₂ = 370 s
What happens to warm air when it cools?
A
It sinks back down to Earth.
B
It is absorbed into clouds.
с
It remains in Earth's upper atmosphere.
D
It breaks apart and disappears.
Answer:
b I'm pretty sure sorry if I'm wrong
Answer:
I think the answer is B
Explanation:
The warm air turns cold and then it goes back to clouds
Two students are sitting 1.50 m apart. One student has a mass of 70.0 kg and
the other has a mass of 52.0 kg. What is the gravitational force between them?
A. 8.01 x 10-9
B. 1.08 x 10-2
C. 2.28 x 10-8
Answer:
B
Explanation:
An object carries a +15.5 uC charge.
It is 0.525 m from a -7.25 uC charge.
What is the magnitude of the electric
force on the object?
Answer:
3.67 N
Explanation:
From the question given above, the following data were obtained:
Charge of 1st object (q₁) = +15.5 μC
Charge of 2nd object (q₂) = –7.25 μC
Distance apart (r) = 0.525 m
Force (F) =?
Next, we shall convert micro coulomb (μC) to coulomb (C). This can be obtained as follow:
For the 1st object
1 μC = 1×10¯⁶ C
Therefore,
15.5 μC = 15.5 × 1×10¯⁶
15.5 μC = 15.5×10¯⁶ C
For the 2nd object:
1 μC = 1×10¯⁶ C
Therefore,
–7.25 μC = –7.25 × 1×10¯⁶
–7.25 μC = –7.25×10¯⁶ C
Finally, we shall determine the force. This can be obtained as follow:
Charge of 1st object (q₁) = +15.5×10¯⁶ C
Charge of 2nd object (q₂) = –7.25×10¯⁶ C
Distance apart (r) = 0.525 m
Electrical constant (K) = 9×10⁹ Nm²/C²
Force (F) =?
F = Kq₁q₂ / r²
F = 9×10⁹ × 15.5×10¯⁶ × 7.25×10¯⁶ / 0.525²
F = 3.67 N
Therefore, the force on the object is 3.67 N
A wheel rotates about a fixed axis with an initial angular velocity of 24 rad/s. During a 4 s interval the angular velocity decreases to 14 rad/s. Assume that the angular acceleration is constant during the 4 s interval. How many radians does the wheel turn through during the 4 s interval
Answer:
[tex]\theta=76\ rad[/tex]
Explanation:
Hoven that,
Initial angular velocity of the wheel = 24 rad/s
Final angular velocity = 14 m/s
Time, t = 4 s
We need to find how many radians does the wheel turn through during the 4 s interval. Let the displacement is [tex]\theta[/tex]. Using second equation of rotational kinematics to find it such that,
[tex]\theta=\omega_i t+\dfrac{1}{2}\alpha t^2[/tex]
Where
[tex]\alpha[/tex] is angular acceleration
[tex]\alpha =\dfrac{\omega_f-\omega_i}{t}\\\\\alpha =\dfrac{14-24}{4}\\\\\alpha =-2.5\ rad/s^2[/tex]
So,
[tex]\theta=24\times 4+\dfrac{1}{2}\times (-2.5)\times 4^2\\\\\theta=76\ rad[/tex]
So, it will turn 76 radian during the 4 s interval.
A 10 kg box initially at rest is pulled with a 50 N horizontal force for 4 m across a level surface. The force of friction
acting on the box is a constant 20 N. How much work is done by the gravitational force?
A. 03
OB. 10 J
C. 100
D. 50 J
Answer:
B i think
Explanation:
...
What causes an electric field?
Answer: The electric field is produced by stationary charges, and the magnetic field by moving charges (currents); these two are often described as the sources of the field. ... The force created by the electric field is much stronger than the force created by the magnetic field.
Explanation: An electric field is an invisible force field created by the attraction and repulsion of electrical charges (the cause of electric flow), and is measured in Volts per meter (V/m).
Answer:
The electric field is produced by stationary charges, and the magnetic field by moving charges (currents); these two are often described as the sources of the field. The force created by the electric field is much stronger than the force created by the magnetic field.
Explanation:
Ggl
The angle between reflected ray and the normal line is
Answer:
Explanation:
angle of incidence.
A mom pushes her 19.3 kg daughter on the swing. If she gives her an initial velocity of 7.5 m/s at the bottom of the swing and the swing sits 0.6 m above the ground at it's lowest point, what height does she reach above the ground?
Answer:
3.17333333333? I hope I get it right
Explanation:
..................hello