A block is released from rest at the top of a hill of height h. If there is negligible friction between the block and the hill, the block arrives at the bottom of the hill with speed v.
Answer:
v / √2
Explanation:
A blocked from rest at the top of a hill of height h it there is negligible friction between the block and the hill, the block arrives at the bottom of the hill with speed. The block is released from rest at the top of another hill with a rough surface and height h. if one-half of the initial mechanical energy of the block Earth System is lost due to friction as the block descends the hill, the block will reach the bottom of the hill with a speed of?
Solution:
For the first block block, its potential energy at the top of the hill when it is at rest is converted to kinetic energy after release with a velocity v.
The kinetic energy = (1/2)mv², where m is the mass of the block.
For the other block placed on the top of the rough hill, the mechanical energy (kinetic energy) is halved due to the roughness of the hill. If u is the speed of this block at the bottom of the hill then:
kinetic energy of block on the rough hill = (1//2)mu²
Hence:
(1//2)mu² = half of main system kinetic energy
(1//2)mu² = 1/2 * (1/2)mv²
mu² = (1/2)mv²
u² = (1/2)v²
u = √(v²/2)
u = v / √2
Hence the speed at the bottom of the rock of the block placed on the rough surface is v / √2
Nore ordered an ice cream cone.
Answer:
okay
Explanation:
okay
Answer:
Cool
Explanation:
what polarity must the red tip of the compass needle be since it points toward the south pole of the magnet?
Answer: positive
Explanation: because opposites attract and north=positive and south=negative the answer should be positive.
The polarity of the red tip of the compass needle must be at the north of the earth, since it points toward the south pole of the magnet.
What is meant by polarity of a magnet ?Polarity of a magnet is defined as the orientation of both the north and south poles of the magnet in space.
Here,
We know that, the opposite poles attract.
The magnetic needle is arranged in a such a way that, the red tip of the magnetic compass needle is actually pointing towards the geographic north pole of the earth.
In order to point the compass needle towards the magnetic south pole, the south pole of the magnet must be located in the geographic north pole.
Hence,
The polarity of the red tip of the compass needle must be at the north of the earth, since it points toward the south pole of the magnet.
To learn more about polarity of magnet, click:
https://brainly.com/question/15329793
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Starting from rest, a spinning disk accelerates constantly to a final rotational speed, ω , in a period of time, Δ Δ t. What expression best represents the revolutions the disk has turned through? A) ω Δ Δ t /2 π B) Δ4 ω Δ t 4 π C)Δ22 ω Δ t 2 2 D) Δ ω Δ t E) 2Δ 2 π ω Δ t
Answer:
the correct one is B, θ = [tex]\frac{1}{4\pi }[/tex] w t [rev]
Explanation:
This is a rotational kinematics exercise
w = w₀ + α t
w² = w₀² + 2 α θ
indicate that part of rest whereby the initial angular velocity is zero
w = α t -> α = w/t
w² = 2 α θ
we substitute
w² = 2 (w / t) θ
w = 2 θ / t
θ = w t / 2
This angle is given in radians, let's reduce to revolutions = 2π rad = 1 rev
θ = w t / 2 rad (1 rev / 2π rad)
θ = [tex]\frac{1}{4\pi }[/tex] w t [rev]
when checking the answers, the correct one is B, even though he has some mistakes in his writing
(please awnser i need my grade up) We can calculate the about of potential energy in an object using the formula PE = mgh where m is the mass of the object, g is the acceleration due to gravity (which on Earth is a constant 9.8) and h is the height the object is from ground. If I have a 2kg bar of gold and raise that to a shelf mounted 3 meters from the ground what is that objects GPE? Remember to insert the numbers into the formula like this PE = (2) (9.8) (3) , you may use your calculator to complete this multiplication problem.
Answer:
88.2 J
Explanation: Hope I helped <3
what makes up a atom
Answer:
They're typically made up of three main parts: protons, neutrons and electrons. Think of the protons and neutrons as together forming a “sun”, or nucleus, at the centre of the system. The electrons orbit this nucleus, like planets. If atoms are impossibly small, these subatomic particles are even more so.
Explanation:
hope i helped.
Answer:
Atoms consist of a nucleus made of protons and neutrons orbited by electrons. ... We now know that atoms are made up of three particles: protons, neutrons and electrons — which are composed of even smaller particles, such as quarks.
Explanation:
Please do all of i will give you brainlest and thanks to best answer plz do it right
Answer:
winter solstice i think
Explanation:
Answer:
a/ solar eclipse
Explanation:
because the moon is on the left side of earth
A red 120 kg bumper car moving at 4 m/s collides with a green 100 kg bumper car moving at 3 m/s. The red bumper car bounces off at 2 m/s. What is the green car's final velocity?
A car travels 14 km due west, then does a
U-turn, and travels 43 km due west.
I. What total distance has the car
traveled?
II.
What is the total displacement of the
car?
III. If the entire trip took 3.20 hours.
determine the average speed of the
car. Give
your answer in both
km hour, and m s. (show
conversion)
IV. If the entire trip took 2.50 hours.
determine the average velocity of
the car. Give your answer in both
km h, and mph (show conversion)
Explanation:
It is given that,
A car travels 14 km due west, then does a U-turn and travels 43 km due east (when it takes U-turn, it will change direction from west to east)
i. Total distance = total path covered
= 14 km + 43 km
= 57 km
ii. Let east is positive and west is negative.
Displacement = final position-initial position
= 43-14
= 29 km
iii. If time taken in the entire trip = 3.2 hours
Average speed = distance/time
[tex]s=\dfrac{57\ km}{3.2\ h}\\\\=17.81\ km/h[/tex]
1 km/h = 0.2777 m/s
17.81 km/h = 4.94 m/s
iv. If time taken in the entire trip = 2.5 hours
Average velocity = displacement/time
[tex]v=\dfrac{29\ km}{2.5\ h}\\\\=11.6\ km/h[/tex]
1 km/h = 0.621 mph
11.6 km/h = 7.2 mph
Henc, this is the required solution.
Mary and Carl drove to the store to shop Their trip to the store time at the store and trip home is graphed here. What was their
Average speed for the entire trip
A) 15 km/h
B)30 km/h
C) 60 km/h
D) cannot tell from this data
Answer:
Option B. 30 Km/h
Explanation:
To solve this question, we must know the meaning of average speed.
Average speed is simply defined as the total distance travelled divided by the total time taken to cover the distance. Mathematically, it is expressed as:
Average speed = Tota distance /Total time
Thus, with the above formula, we can obtain the average speed of the entire trip as shown below:
Total distance = 60 Km
Total time = 2 h
Average speed = Total distance /Total time
Average speed = 60 /2
Average speed = 30 Km/h
Thus, the average speed of the entire trip is 30 Km/h
Answer:
I think it is B maybe A
Explanation:
How does eclipses occur
Answer:
When Earth passes directly between the sun and the moon, a lunar eclipse takes place. During a solar eclipse, the moon casts two shadows. One is called the umbra; the other is called the penumbra. An eclipse takes place when Earth or the moon passes through a shadow.
A car travels east at a constant velocity. The net force on the car is:
A child kicks a ball horizontally with a speed of 4.8 m/s off a deck 3.5 m off the ground. How far, in meters, from the deck does the ball land on the ground?
Answer:
2.605m
Explanation:
Using the formula for calculating Range (distance travelled in horizontal direction)
Range R = U√2H/g
U is the speed = 4.8m/s
H is the maximum height = ?
g is the acc due to gravity = 9.8m/s²
R = 3.5m
Substitute into the formula and get H
3.5 = 4.8√2H/9.8
3.5/4.8 = √2H/9.8
0.7292 = √2H/9.8
square both sides
0.7292² = 2H/9.8
2H = 0.7292² * 9.8
2H = 5.21
H = 5.21/2
H = 2.605m
Hence the height of the ball from the ground is 2.605m
an object increases its velocity from 22 m/s to 36 m/s in 5s.what is the acceleration of the object
Answer:
2.8 m/s²
Explanation:
v=v0+at <=> 36 = 22 + a×5 <=> 5a = 36-22 <=> 5a = 14 <=> a = 14/5 <=>
<=> a = 2.8 m/s²
4. A Ferrari travels 350km in 2 hours. What was it's
s speed?
Don't mind this, just figuring something out
Answer:
ok
Explanation:
Have a nice day!
6th grade science I mark as brainliest.
Answer:
divide 10 by 50.
Explanation:
Because its time over speed 10/50
5 meter/ second
I think it's helpful
follow me and don't forget to Mark me as brainlist please
As the amount of surface area increases, what happens to the rate of this reaction? If the antacid tablet were broken into eight pieces, what would be a reasonable estimate for the time of
as the surface area increases the rate of reaction also increases.
Explanation:
Answer:
A.) The rate is faster.
C.) 28 Seconds
a lift travelling up to the top floor of the empire state building with a mass of 4200kg and a kenetic energy of 4116 J
Though the question does not ask for anything, I'll assume you need to calculate the speed of the lift.
Answer:
The lift travels at 1.4 m/s
Explanation:
Kinetic Energy
Is the type of energy of an object due to its state of motion. It's proportional to the square of the speed and the mass.
The equation for the kinetic energy is:
[tex]\displaystyle K=\frac{1}{2}mv^2[/tex]
Where:
m = mass of the object
v = speed at which the object moves
The kinetic energy is usually expressed in Joules (J)
If we already know the value of the kinetic energy, we can find the speed by solving for v:
[tex]\displaystyle v=\sqrt{\frac{2K}{m}}[/tex]
The lift has a mass of m=4200 Kg and has a kinetic energy of K=4116 J, thus it's moving at a speed of:
[tex]\displaystyle v=\sqrt{\frac{2*4116}{4200}}[/tex]
[tex]\displaystyle v=\sqrt{1.96}[/tex]
v = 1.4 m/s
The lift travels at 1.4 m/s
Suppose you are in a moving car and the motor stops running. You step on the brakes and slow the car to half speed. If you release your foot from the brakes, will the car speed up a bit, or will it continue at half speed and slow due to friction?
Answer:
See the answer below
Explanation:
If you step on the brake of a car while driving, the frictional force between the tires of the car and the surface of the road increases in opposition to the motion of the car. Consequently, the car slows down.
If you release your foot from the brake pedal when the car is still at half speed, the frictional force reduces and the car speeds up a bit even without pressing the throttle. Eventually, the frictional force will slow down and stop the car if the throttle is not pressed.
Calculate the gravitational potential energy of a 2 kg banana hanging 5
meters above the ground.
(Use 10 m/s2 for gravity)
Answer:
100 J
Explanation:
The potential energy is given by the formula ...
PE = mgh
= (2 kg)(10 m/s^2)(5 m) = 100 J
Which of the following would be an example of mechanical energy?
Elastic Energy, Kinetic Energy, Gravitational Potential Energy
Gravitational Potential Energy, Thermal Energy
Electric Potential Energy, Nuclear Energy, Kinetic Energy
Magnetic Energy, Elastic Potential Energy
Answer:
A) Elastic Energy, Kinetic Energy, and Gravitational Potential Energy
Explanation:
Hope this helps!
Will mark brainiest!!!
1. A __ is caused by a sudden shift in the ocean crust which displaces the water. *
2. A tsunamis is possible, but unlikely at a __ plate boundary where two plates are moving sideways past each other. *
3. A Shallow __ is a good indicator of tsunamis, but sends data very slowly and cannot detect earthquakes. *
4. Tsunamis are common at __ plate boundaries, since large earthquakes release the built up pressure, resulting in a quick vertical movement of the plate. *
5. The Indonesian Earthquake of 2004 had a 9.1__, which was the third largest ever recorded in human history. *
All possible answers:
A. Earthquake
B. Tsunami
C. Magnitude
D. Sensor
E. Transform
F. Convergent
G. Divergent
Answer:
1. Tsunami
2.Divergent
3.Sensor
4.Convergent
5.Magnitude
Explanation:
18. Which would be the most reliable source of information to use for a history report? (2 points)
O An encyclopedia
O A magazine article
O A newspaper
A TV show
Answer:
encyclopedia most reliable I think
A 0.85-kg arrow flies through the air at a speed of 19 m/s. What is the momentum of the arrow?
16 kg m/s
22 kg m/s
160 kg m/s
360 kg m/s
Answer:
16 kg m/sExplanation:
The momentum of an object can be found by using the formula
momentum = mass × velocity
From the question we have
momentum = 0.85 × 19 = 16.15
We have the final answer as
16 kg m/sHope this helps you
An astronaut rides in a circular training accelerator at 16 m/s. If the radius of the accelerator is 8.0 meters, what is his centripetal acceleration? m/s2 Enter the answer Submit Answer I don't know this mprove this question
Answer:
[tex]a=32\ m/s^2[/tex]
Explanation:
Given that,
The velocity of an astronaut in a circular path, v = 16 m/s
The radius of the accelerator, r = 8 m
We need to find his centripetal acceleration. The formula that is used to find the centripetal acceleration is given by :
[tex]a=\dfrac{v^2}{r}\\\\a=\dfrac{(16)^2}{8}\\\\a=32\ m/s^2[/tex]
So, the required centripetal acceleration is [tex]32\ m/s^2[/tex].
A pitcher throws a ball toward a player holding a softball bat. The bat applies a 10-Newton force to the ball. Which statement correctly describes the reaction force between the bat and the ball?
Answer:
The reaction force is the force that causes the ball to move toward the bat.
Explanation:
Answer:
D; the reaction force is the force of the ball on the bat.
Explanation:
Thermal energy can not be transferred or transformed into other forms of energy.
O True
False
Answer:
I believe it is false I took the test
Answer:
false
Explanation:
3. What is the best way to help with
mining problem in the future?
Answer:
1) Mining companies have an impressive track record for delivering continuous improvements in safety and risk governance standards. We have no doubt that the professionalism and expertise present within the industry will ensure that any new and emerging risk challenges are dealt with in an equally determined fashion.
2) Insurers have recognized the approach and achievements of mining companies in identifying, mitigating and retaining their risks. Many mining companies have close and longstanding relationships with their insurers built through regular dialogue with mining company executives and visits to mining sites and processing facilities.
3) This document should be of value to any organization involved in this ever-evolving industry.
4) The very nature of mining natural resources means that many businesses will have operations in some of the most remote and inhospitable areas in the world and very often coupled with a high susceptibility to natural catastrophe.
5) In addition to the traditional risk factors, the mining industry now faces an even wider range of challenges. Factors such as climate change, new technologies, economic uncertainties and secure supply of key consumables like electricity, water, gas and other fuels are all difficult to predict and bring additional complications to securing appropriate balance sheet protection.
Which of the following is a warning sign of an abusive relationship?
Answer: The choices?
Explanation:
