Given :
Initial velocity, u = -15 m/s.
Acceleration , a = 2 m/s².
Time taken to applied brake, t = 2.5 s.
To Find :
The velocity of the car at the end of the braking period.
How far has the car moved during the braking period.
Solution :
By equation :
[tex]v = u+at\\\\v=-15 + 2\times 2.5\\\\v=-10 \ m/s[/tex]
Now, distance covered by car is :
[tex]s=ut+\dfrac{at^2}{2}\\\\s=(-15)(2.5)+\dfrac{2(2.5)^2}{2}\\\\s=-31.25\ m[/tex]
Hence, this is the required solution.
A train rolls at a constant speed of 10 m/s across a horizontal track. A child standing on the flatbed of the train throws a ball so that it appears to move straight up to an observer standing next to the track. a. What is the horizontal speed of the ball relative to the observer?
Answer:
The answer is 10m/sExplanation:
Given that the child is in the train, and that the train is moving at a speed of 10m/s, and also the child is standing on the flatbed, hence the child is not moving, therefore the velocity of the child is 10m/s relative to the observer
Also, when the child throws the ball horizontally relative to the observer the horizontal speed is also 10m/s.
therefore the speed of the ball is also 10m/s to the observer
Find the acceleration of a car with a mass of 1,200kg and a force of 11,000N
Answer:
42000N
Explanation:
.........................
protons are present in sodium atom.
a 11
b 10
C 12
d 9
11
Explanation:
There are 11 protons in a sodium atom
Max and Jimmy want to jump on a trampoline. Max begins jumping in a steady pattern, making small waves in the trampoline. Jimmy starts jumping on the trampoline too. Suddenly, Max goes twice as high even though he did not put any extra effort into jumping. What type of wave interaction is this?
Answer:
x_total = (A + B) cos (wt + Ф)
we have the sum of the two waves in a phase movement
Explanation:
In this case we can see that the first boy Max when he enters the trampoline and jumps creates a harmonic movement, with a given frequency. When the second boy Jimmy enters the trampoline and begins to jump he also creates a harmonic movement. If the frequency of the two movements is the same and they are in phase we have a resonant process, where the amplitude of the movement increases significantly.
Max
x₁ = A cos (wt + Ф)
Jimmy
x₂ = B cos (wt + Ф)
total movement
x_total = (A + B) cos (wt + Ф)
Therefore we have the sum of the two waves in a phase movement
Answer:
In this case we can see that the first boy Max when he enters the trampoline and jumps creates a harmonic movement, with a given frequency. When the second boy Jimmy enters the trampoline and begins to jump he also creates a harmonic movement. If the frequency of the two movements is the same and they are in phase we have a resonant process, where the amplitude of the movement increases significantly.
Explanation:
Define what velocity means.
Answer:
The velocity of an object is the rate of change of its position with respect to a frame of reference, and is a function of time. Velocity is equivalent to a specification of an object's speed and direction of motion (e.g. 60 km/h to the north).
When a Newton's Cradle with three marbles is pulled back and released, a collision happens between the marbles causing a cycle of repeated motion. This transfer of energy will last for several cycles. List out all of the energy transfers that occur in one cycle.
Answer:
Please find the answer in the explanation
Explanation:
When a Newton's Cradle with three marbles is pulled back and released, the mechanical energy is converted to potential elastic energy.
When a collision happens between the marbles causing a cycle of repeated motion, The elastic potential energy is converted to kinetic energy.
This transfer of energy will last for several cycles. If there is any energy lost, then the kinetic energy must have been converted to thermal energy or heat energy
21000 km/hr how far will it travel in 5 hours
Answer:
105000 is the answer your welcome
Explanation:
105000
Why does sonar use ultrasound rather than sound?
Answer; Ultrasonic waves (sounds having frequency greater than 20,000 Hz) are used in sonar because: ... Ultrasonic waves can penetrate water to long distances (because of their high frequency and very short wavelength), but ordinary sound waves or infrasonic waves cannot penetrate water to such long distances.
Answer:
Ultrasonic waves (sounds having frequency greater than 20,000 Hz) are used in sonar because: ... Ultrasonic waves can penetrate water to long distances (because of their high frequency and very short wavelength), but ordinary sound waves or infrasonic waves cannot penetrate water to such long distances
Explanation:
A dog is 60 m away while moving at a constant velocity of 10 m/s towards you. How Long will it be before the dog is close enough to your face?
Answer:
6 seconds
Explanation:
The answer is 6 because if the dog is going 10 m/s it will take 6 seconds to get from 60 meters away to you.
Use the drop-down menu to identify the state of matter represented by each imagine.
A.
B.
C.
D.
Answer:
a: gas
b: solid
c: liquid
d: plasma
Explanation:
Answer:
Each image displays a different state of matter.
Use the drop-down menu to identify the state of matter represented by each image.
A:
✔ gas
B:
✔ solid
C:
✔ liquid
D:
✔ plasma
Explanation:
got it right
Plz I need the answer quick!!!
What is the definition of law of conservation of energy
Answer:
The law of conservation of energy states that energy can neither be created nor destroyed - only converted from one form of energy to another. This means that a system always has the same amount of energy, unless it's added from the outside. This is particularly confusing in the case of non-conservative forces, where energy is converted from mechanical energy into thermal energy, but the overall energy does remain the same. The only way to use energy is to transform energy from one form to another.
Explanation:
Hope this helps!
Answer:
means that energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another.
Explanation: this is a shorter answer.
An object is moving east with a constant speed of 30 m/s for 5 seconds. What is the object’s acceleration?
Answer:
6 m/s²
Explanation:
From the question given above, the following data were obtained:
Velocity (v) = 30 m/s
Time (t) = 5 s
Acceleration (a) =..?
Acceleration is defined mathematically as:
Acceleration (a) = Velocity (v) /time (t)
a = v /t
With the above formula, we can obtain the acceleration of the object as follow:
Velocity (v) = 30 m/s
Time (t) = 5 s
Acceleration (a) =..?
a= v/t
a= 30/5
a = 6 m/s²
Therefore, the acceleration of the object is 6 m/s² due East.
Which is inversely proportional to your weight on a planet's surface?
A. Only your mass
B. Your mass and the mass of the planet
O O O
C. Only the planet's mass
D. The distance from the surface to the center of the planet
Answer:
most likely D
Explanation:
Distance from the surface to the center of the planet is inversely proportional to your weight or force due to gravity on a planet's surface.
What is force?A force is an effect that can alter an object's motion according to physics. An object with mass can change its velocity, or accelerate, as a result of a force. An obvious way to describe force is as a push or a pull. A force is a vector quantity since it has both magnitude and direction.
The gravitational constant, denoted by the capital letter G, is an empirical physical constant involved in the calculation of gravitational effects in Sir Isaac Newton's law of universal gravitation and in Albert Einstein's theory of general relativity.
f = Gmm/r²
Distance from the surface to the center of the planet is inversely proportional to your weight or force due to gravity on a planet's surface.
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If all objects that have mass also have gravity, why doesn't your pencil get pulled towards you while it sits on your desk?
Answer:
The pencil is not pulled towards a person due to a very small magnitude of force between them, due to lighter masses.
Explanation:
Let us apply Newton's Law of Gravitation between a person and pencil.
Average Mass of a Normal Pencil = m₁ = 10 g = 0.01 kg
Average Mass of a Person = m₂ = 80 kg
Distance between both = r = 1 cm = 0.01 m (Taking minimal distance)
Gravitational Constant = G = 6.67 x 10⁻¹¹ N.m²/kg²
So,
F = Gm₁m₂/r²
F = (6.67 x 10⁻¹¹ N.m²/kg²)(0.01 kg)(80 kg)/(0.01 m)²
F = 5.34 x 10⁻⁷ N
This Force is very small in magnitude due to the light masses of both objects.
Therefore, the pencil is not pulled towards a person due to a very small magnitude of force between them, due to lighter masses.
pts
You walk 10 meters east, then 5 meters north. What is your displacement?
In the real world could the roller coaster car reach the top of the second hill if the second hill were as high as the firsts hill
Answer: No, it couldn’t. Energy leaves the system in the form of heat as the roller coaster cars travel from the top of one hill to the next. The vehicles have less total energy, so the potential energy at the top of the second hill must also be less. The cars wouldn’t be able to achieve the height of the first hill.
Explanation: Make sure to change some of it because it's from Edmentum!!
what would a boats velocity be if it would go 15kph and 18 kph?
Answer:
It depends
Explanation:
That
Vhy do people engage in various
e long answer to the following questions.
Which tradition of our society needs to be reform
and write the ways to reform them
of Nepal
How do electromagnetic waves affect you?
Answer:
At low frequencies, external electric and magnetic fields induce small circulating currents within the body. ... The main effect of radiofrequency electromagnetic fields is heating of body tissues. There is no doubt that short-term exposure to very high levels of electromagnetic fields can be harmful to health.
The town of Seaside needs to build a new power plant. The old coal burning plant produces too much pollution and is no longer safe. The mayor decides that he will do some research on alternative forms of energy like nuclear power plants and solar power plants.
What types of resources should the mayor use to conduct his research? Why would these be considered reliable sources of information and why? What types of resources are reliable? How can he use what he learns to make the best decision for the town?
The mayor is making a good decision to do research into renewable forms of energy. Not only does coal produce pollution, it also contributes to greenhouse gas emissions. Plus, the supply of coal is a finite source. It is considered a natural resource instead of renewable. That means that eventually the supply of coal will run out at some point. Renewables do not encounter such a problem.
So it's smart to look into alternative forms of energy such as nuclear or solar. The benefit of nuclear is that it produces a lot of energy and does so efficiently. The downside is that it's that accidents would lead to disastrous outcomes (eg: the nuclear disaster in Japan). Also, there's the issue of what to do with the nuclear waste. The waste itself is very dangerous and it must be buried underground sealed in thick containers. This is an expensive operation. The rate of decay of the material takes a long time, which means that future generations hundreds of years down the line will have to deal with the waste.
Solar is a cleaner alternative to nuclear, but unfortunately it is not as efficient compared to nuclear power. You need a lot of solar panels in a vast open area to be able to get the energy to power many homes. Places out in the desert are a good choice to put the solar farms because the sun shines intensely there and not many people (or no people) live out in remote areas such as that one.
Because the town is called Seaside, it seems like this town is on the coast. If so, then the mayor should look into wind power to complement solar power. Wind along the coast is often very intense due to the sea current and jet stream. The downside to wind power is that some days the wind doesn't blow at all. The mayor could also look into tidal power which harnesses the flow of the tides coming in and out. If a major river is nearby (that flows into the ocean) then s/he could consider hydroelectric power as well. There are many renewable options to pick from. Each option has its pros and cons, so it's up to the mayor to weigh what exactly their needs are and how efficiently they want electricity. Mixing various options is possibly the best idea since you get a bit of each pro/con from all the options mentioned.
can we add 2 atoms together? 3? How do particles combine to form the variety of matter one observes?
A piece of metal has a density of 11.3 g/cm and a volume of
6.7 cm3. What is the mass of this piece of metal?
Answer:75.71g≈75.7
Explanation:Mass = Density ⋅ Volume = 11.3 ⋅ 6.7 = 75.71g
4. Which of the following statements is correct?
A Mass and weight are different names for the same thing
B The mass of an object is different if the object is taken to the Moon
C The weight of a cer is one of the forces acting on the car.
D The weight of a chocolate beris measured in kilograms
Answer:
Explanation:
A: wrong. Mass and weight are different.
B: Wrong. The mass here and the mass on the moon are the same. The weight, which is Mass * the acceleration is equal to weight.
C: Correct.
D: Wrong. Weight is not measured in Kg. Mass is.
A student wants to shorten the ripening time for tomatoes. He predicts that the more water the seedlings receive, the faster the tomatoes will ripen. He grows 20 tomato plants in a garden with full sunlight that has dry soil and 20 tomato plants in the same garden where there is more moisture in the soil. He records the time it takes for fruit to develop and ripen on the plants in each location. What is the test variable (independent variable) in this experiment?
Answer:
Moisture
Explanation:
The independent variable, in this case, would be the moisture levels of the soils.
The independent variable is the variable being tested. It is the only variable that is altered in the course of an experiment and which has a direct effect on the actual variable that is the main aim of the experiment. All other variables are kept constant while the independent variable is manipulated.
The tomato plants in the two groups were under the same conditions except that a group had more moisture in the soil. Hence, the independent variable is the moisture.
What are the 8 types of energy? SOMEONE PLEASE PLEASE HELP
thermal energy, radiant energy, chemical energy, nuclear energy, electrical energy, motion energy, sound energy, elastic energy and gravitational energy
The eight types of energy are Kinetic Energy, Potential Energy, Thermal Energy, Chemical Energy, Electrical Energy, Radiant Energy, Nuclear Energy, and Sound Energy.
The eight types of energy are:
Kinetic Energy: The energy possessed by an object due to its motion.
Potential Energy: The energy stored in an object based on its position or condition.
Thermal Energy: The energy associated with the motion of particles in a substance. It is related to temperature.
Chemical Energy: The energy stored in the bonds of chemical compounds.
Electrical Energy: The energy associated with the movement of electric charges.
Radiant Energy: The energy carried by electromagnetic waves, such as light or radio waves.
Nuclear Energy: The energy released or absorbed during nuclear reactions or radioactive decay.
Sound Energy: The energy produced by the vibration of objects and transmitted through a medium as sound waves.
These are the commonly recognized types of energy. It's important to note that energy can often be converted from one form to another.
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How are velocity, wavelength, and frequency related
Answer:
The wave velocity and the wavelength are related to the wave's frequency and period by vw=λT or vw=fλ. The time for one complete wave cycle is the period T. The number of waves per unit time is the frequency ƒ. The wave frequency and the period are inversely related to one another.
Explanation:
A group of tourists drives through a state park in Maine. While arguing about whether the animal they've just seen is an Elk or a Moose, a chipmunk darts across the park road. The driver, who was traveling 6.7 m/s through the park slams on their breaks and comes to a stop. If the car has an acceleration of -8.3 m/s2, how long does it take the car to stop?
Answer:
0.8 second
Explanation:
Given data
Speed v=6.7m/s
Deceleration = - 8.3m/s²
Initial velocity u= 0m/s
We can solve for the distance covered upon breaking the speed using the expression
v=u +at
6.7=0-(8.3)t
6.7=8.3t
Divide both sides by 8.3
6.7/8.3=t
t=6.7/8.3
t=0.8 second
field lines point out from all sides on a object. Some of the lines point into a second object nearby. Which statement best describes the objects? A. both objects are permanent magnets B. both objects are electromagnets C. the first object is negatively charged, and the second object is positively charged D. the first object is positively charged, and the second object is negatively charged
Answer:
The first object is positively charged, and the second object is negatively charged. (D)
Explanation:
List two objects here on Earth that are sources of radiant energy. How can you tell they emit radiant energy?
When an object is said to be in free fall, the object is actually moving..