You accidentally throw your car keys horizontally at 8.0 m/s from a cliff. If yours keys land 28 m from the base of the cliff, how high was the cliff? Question 10 options: 17.15 m 60 m 45 m 28 m
Answers
Answer:
[tex]45m[/tex]
Explanation:
Let [tex]V_0[/tex] be the horizontal speed of the keys and D be the horizontal distance covered by the keys.
[tex]V_0= 8.0 \frac ms[/tex]
[tex]D= 28 m[/tex]
The initial velocity in the vertical direction is [tex]0[/tex].
Let [tex]g[/tex] be the acceleration due to gravity, which always acts vertically downwards, so, it will not change the horizontal direction of the speed, i.e. [tex]V_0[/tex] will remain constant throughout the projectile motion.
Let [tex]t[/tex] be the total time of flight in seconds. So,
[tex]D= V_0t[/tex]
[tex]\Rightarrow 28=8t[/tex]
[tex]\Rightarrow t=3 s \; \cdots (i)[/tex]
Let [tex]H[/tex] be the hight of the cliff.
Now, from the equation of motion
[tex]s=ut+\frac 1 2 at^2\;\cdots(ii)[/tex]
Where is the displacement is the direction of force, is the initial velocity in the direction of force, is the constant acceleration due to force and is the time of flight.
Here, , and (negative sign is for taking the sigh convention positive in the direction as shown in the figure.)
From equation (ii)
[tex]-H=0\times t + \frac 1 2 (-g)t^2[/tex]
[tex]\Rightarrow H= \frac 1 2 gt^2[/tex]
Take [tex]g= 10 \frac m{s^2}[/tex] and put the value of [tex]t[/tex] from equation (i), we have
[tex]H=\frac 1 2 \times 10\times 3^2[/tex]
[tex]\Rightarrow H= 45 m[/tex].
Hence, the height of the cliff was [tex]45 m[/tex].
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Answer:
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Explanation:
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Answer:
a scientific law must be universally correct there could be no contradictions regarding the law anywhere
Describe all of the forces acting on the ice cream in the root beer float. Relate these forces to the fact that the ice cream is floating
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Answer: Sample Response: The root beer exerts a force on all sides of the ice cream. These forces are all equal and cancel each other out. Gravity pushes downward on the ice cream. This can also be called the weight of the ice cream. Buoyant force pushes the ice cream upward. The ice cream floats because the buoyant force is greater than the weight of the ice cream.
Answer:
The root beer exerts a force on all sides of the ice cream. These forces are all equal and cancel each other out. Gravity pushes downward on the ice cream. The ice cream floats because the buoyant force is greater than the weight of the ice cream.
Explanation:
A rowboat that is traveling 2.5m/s to the north, encounters a current traveling 4.3m/s to the east. What is the resultant velocity of the rowboat, including the angle?
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what is acceleration of a 12 kg cart if a net force of 144 N is applied on it?
Answers
Answer:
The correct answer is I just did the quiz
Force,F=144N
Mass,m=12Kg
Force=Mass*Acceleration
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A car enters a freeway with a speed of 6.5 m/s and accelerates to a speed of 24 m/s in 3.5 min. How far does the car travel while it is accelerating? (Hint: find the acceleration first)
a 3205.5 m
b 1548.75 m
c 76.13 m
d 761.3 m
Answers
Explanation:
Using Equations of Motion :
(1) v = u + at
24 = 6.5 + a * 210
a (Acceleration) = 0.083 m/s^2
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(Option A seems a typo since the answer is 3215.3 m)
WILL GIVE BRAINILY TO FIRST PERSON TO ANSWER!!!!
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Answers
The answer is increase.
d = m/v. if you increase the mass without changing the volume, the density will increase.
Does a calculation lose any information when converted from centimeters to meters? Explain
Answers
Answer:
No
Explanation:
There are many units that are used to measure length of an object. For example centimeters, meters, millimeters etc.
There is a relationship between any of two units to measure lengths. If we want to convert some length from cm to m, it can be done as follows :
1 cm = 0.01 m
or
1 m = 100 cm
When we use this conversion, the calculation remains the same. Only the way to represent it will be different.
Hence, there is no lose of information when converted from centimeters to meters.
Which sentence describes Newton's second law?
O A. Two forces are unbalanced if they are unequal or they are not
acting in opposite directions.
O B. When the forces on an object are balanced, the object does not
move.
C. Larger net forces are required to accelerate objects that have
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D. The action force applied by one object to another is equal in
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Answers
Answer: Larger net forces are required to accelerate objects that have more mass
Explanation:
Is the answer C or B
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Answer:
c
Explanation:
though c is wider it has more water.
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Answer:
The answer to your question is 404.2000
A bicycle is going 2.6 m/s when it speeds up to 15.4 m/s in 8 seconds. What is the acceleration?
Answers
Answer:
acceleration is 1.6 m/s^2
Explanation:
This is a question involving Kinematics so we can use one of the kinematic equations.
Given info: Vi= 2.6 m/s. Vf= 15.4 m/s. T= 8s
We need to solve for acceleration
The best equation to use is (Vf = Vi + at) as it contains all the info we need to solve for acceleration.
Now substitute the values given into the equation.
Vf = Vi + at >> 15.4 = 2.6 + a8
Now solve for a by rearranging the equation.
15.4 -2.6= 8a >> 12.8=8a >> 12.8/8= 8a/8 >> 1.6 =a
NOTES:
Acceleration is the rate of increase of velocity
Vf is final velocity or velocity after acceleration/de-accaeleration occurs
Vi is intial velocity or velocity before acceleration or de-accaeleration occurs
Time is time it took for a certain motion to occur.
y
4
3
2
1
+ +
-4 -3 -2 -1
-1
1
1
2.
1 2
-3+
-4-
What is the slope of the line?
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Answer:
easy no cheater
Explanation:
In what ways are plasmas similar to gases? What makes plasmas different than gases?
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Answer:
Like gases, the particles in plasmas are constantly moving at high speeds, and do not have a definite shape or volume. Plasma is formed when the kinetic energy of the molecules in a gas gets very large and the temperature gets very high. This causes electrons to be released by the atom, creating ionized particles, which are positive ions and negative electrons.
Explanation:
Sample Response <3.
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With explanation please
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Answer:
2.3 Nm clockwise
Explanation:
Take counterclockwise to be positive and clockwise to be negative.
∑τ = (3 N) (2.5 m) − (7 N) (1.4 m)
∑τ = 7.5 Nm − 9.8 Nm
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Answer:
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Explanation:
First, as Kwane rubbing his and and iron his clothes using the energy to create heat, that is thermal being transformed.
The rock being thrown uses kinetic energy and due to graviational force of the earth, it is being transformed into Potential Gravitational Energy.
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a.6.1 s
b.3.7 s
c.12.1 s
D.5.4 s
Answers
Answer:
use first equation of motion v=u+at..v is 0..since we have to take him to rest and u is 13.5
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u = 13.5 m/s
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Answers
Answer: metre per second
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Answers
Answer:
Choice B) B There is no net force on the hockey puck.
Explanation:
In case when the hockey puck the slides with the same velocity or constant velocity so the force with respect to the hockey should contain that there is no net force as if the body moves along with the same velocity or the constant velocity so in this case the body acceleration is zero
And according to the newton second law i.e.
F = ma
In case when the acceleration is zero so the net force is zero
Therefore the option b is correct
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Answer:
calculate the volume of each sample by subtracting the intial water volume from the volume after the sample was added . Record the volume of each sample on your chart in mililiters(ML).
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QUESTION: Is there a relationship between height and shoe size? Write a one sentence
summary of your graph.
J
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Answer:
There is no particular relationship between the height and shoe size. But the shoe sizes in males is usually bigger than females. And the shoe size tends to get bigger when the person is taller.
Explanation:
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Explanation:
Just shift everything except r to the other side.
[tex]r = \sqrt{ \frac{3v}{\pi \: h} } [/tex]
see attached photo below!
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Answer:
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Answer:
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What is the average of 255, 242, 245?
Answers
Answer:
The average is 247.33 if it is for the whole number then it is 247
Explanation:
I did it by adding it all together and dividing it by 3
Answer:
247.33 is the average.
Explanation:
To find the average of a set of numbers:
a. add them up.
b. divide by how many numbers there are.
SO:
a. 255 + 242 + 245 = 742.
b. 742 (total) divided by 3 (# of numbers) = 742/3 = 247.33.
Hope this helps!
define the focus of a concave lens
Answers
Answer:
Principal focus of concave lens -
★ The point at which rays parallel to principal axis coming from infinity appear to converge after being refracted from concave lens is called the principal focus of concave lens.
________________________
• Additional information -
★ Principal focus - A number of rays parallel to the principal axis after reflection from a concave mirror meet at a point on the principal axis or appear to come from a point after reflection from a convex mirror on the principal axis. This is called principal focus.
If an object is moving and it changes its position by 2 min
every 4 s starting from the origin, then the position vs. time
graph is:
Answers
Answer: a straight line with a positive slope
Explanation:
If an object is moving and it changes its position by 2 units every 4 s starting from the origin,
What is speed?The total distance covered by any object per unit of time is known as speed. It depends only on the magnitude of the moving object. The unit of speed is meter/second.
Learn more about speed from here If an object is moving and it changes its position by 2 units every 4 s starting from the origin,
speed = distance /time
= 2 units / 4 seconds
= 0.5 units/seconds
Thus, the speed of the object would be 0.5 units /seconds
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the question seems incomplete the complete question is If an object is moving and it changes its position by 2 units every 4 s starting from the origin, then the position vs. time graph is
Plz help
Among one litre boiling water and a red hot glowing nail, which one has more
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Answers
The water. Take the specific heat of steel, estimate the volume of the nail, you know the volume of the water, which has a specific heat of one. Or be obvious. If you dropped a red hot nail into a liter of cold water, what would happen?
Answer:
Water
☆One litre boiling water has more amount of heat because it has much more greater mass than iron nail
I am not sure if its wrong,sorry
but here is the iron nail explanation also
☆A red hot nail has more amount of heat because the density of iron is more than that of water
I need help finding the average acceleration fo tyler and bree
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In general, which factor is NOT critical when beginning an exercise program? A. using appropriate protective equipment during exercise B. finding friends who like to exercise the same way you do C. seeing your doctor for a physical assessment prior to beginning exercise D. choosing clothing that is designed to match your exercise program Please select the best answer from the choices provided.
O A
О В
O C
PLEASE HELP!!!
Answers
Answer:
B. I looked it up I hope it's right
Explanation:
i hope this helps.
Answer:
its obviously C
Explanation:
i smart like dat