4.A force of 40.0 N is needed to compress a spring 0.200 m. A 1.00 x 10-2 kg ball
...
ring.
a) Calculate the work done to compress the spring. (2 marks)
b) What happens to the work done on the spring ? (1 mark)
c) If the spring is released, what happens to the energy of the spring? (1 mark)
d) Calculate the total mechanical energy of the ball at the instant it leaves the spring. (2 marks)
e) What will be the speed of the ball at the instant it leaves the spring? (2 marks)
f) If the ball is fired up into the air by the spring, how much gravitational potential energy will it gain? (1 mark)
g) What will be the maximum height of the ball? (2 marks
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7.Exercise 4) A fair coin is tossed. If it lands heads, a fair four-sided die
is thrown (with values 2,3,4,7). If
...
2,3,4,7). If it lands tails, a fair six-sided die is
thrown (with values 3,4,5,6,7,9). Regardless of which die is used, Alice
eats n grains of rice, where n is the largest prime factor of the die result
(for example, the largest prime factor of 9 is 3).
(a) What is the conditional probability that the coin lands heads, given
that Alice eats three grains of rice?
(b) Suppose that the entire experiment is conducted twice on the following day (starting with a new coin toss on the second run-through).
What is the conditional probability that the coin lands heads on both
run-throughs, given that Alice eats a total of five grains of rice during the two run-throughs?
(Do not count the two grains from part (a) in part (b); we assume
two brand new experiments, each with a new coin toss. Start your
solution by defining a suitable partition of the sample space. Please
use an appropriate notation and/or justification in words, for each
value that you give as part of your solution.)
Exercise 5) Alice and Bob throw an unfair coin repeatedly, with probability 2/5 of landing heads. Alice starts with £2 and Bob starts with £3 .
Each time the unfair coin lands heads, Alice gives Bob £1 . Each time
the unfair coin lands tails, Bob gives Alice £1 . The game ends when one
player has £5 .
(a) Draw a labelled Markov chain describing the problem, and write
down a transition matrix P. Write down the communication classes,
and classify them as either recurrent or transient.
(b) Using the transition matrix, calculate the probability that Alice loses
all of her money in exactly four tosses of the unfair coin.
(c) Calculate the (total) probability that Alice loses all of her money
(before Bob loses all of his).
(d) Calculate the expected (mean) number of tosses of the unfair coin,
for the game to end.
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8.The equation of a helix is x=2 sin 2t, y=2 cos 2t, z=3t.
a) Find the arc length s
...
an arbitrary point (2 sin 2t, 2 cos 2t, 3t) on the helix.
b) Compute the arc length from (0,2,0) to (0,-2,3π/2)
c) Compute the vectors T, N and B at (0,-2,3π/2)
d) Compute the curvature at (0,-2,3π/2)
e) Find the angle between T and the z-axis at (0,-2,3π/2) to the nearest tenth of a degree.
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9.We play a variation of Monty Hall: The contestant is presented with 3 curtains, behind each there's a prize with
...
a prize with probability p independently of the other curtains. The player chooses one curtain
(a) The game host tells the contestant there's a prize hiding behind at least one of the other curtains, and offers the player a chance to change his choice. Should he?
(b) The game host tells the player there's a prize hiding behind exactly one of the other curtains. Should the player change his choice? How does your answer depend on p
(c) How would your answer to section (b) change if there are n curtains in total?
(d) Bonus (4 points): How would your answer to section (a) change if there are 4 curtains in total?
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11.Let A be the set that is defined recursively in the following way:
Basis Case: ( 0 , 1 , 2
...
Recursive Step: if (n,m,r) ∈ A then (n+1,m+2,m+r+2) ∈ A
Prove, using structural induction, that for every .( n , m , r ) ∈ A , 0 ≤ n < m and n + m ≤ r .
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12.1) Which of the following statements about scientific methods / theories is correct?
(1/0/0)
a) A scientific theory must be able to
...
a) A scientific theory must be able to be proven.
b) A scientific theory has been derived from known facts and always applies.
c) A scientific method should give different results depending on who performs the method.
d) Knowledge of our surroundings usually emerges through an interplay between theory and experiment.
2) The sides of a straight block are measured to 3,202 cm; 0.0012 cm and 11.2 cm, respectively. Calculate the volume of the straightening block and enter it with the correct number of value digits.
(2/0/0)
Number of words: 0
3) A 9.2 dm long and evenly thick rod rests on a support. 0.55 dm from one end, a dynamometer is hung so that the rod will hang horizontally. Then the dynamometer shows 4.4 N. How much does the bar weigh?
(1/1/0)
Number of words: 0
4) A bar AB that is homogeneous and evenly thick has a length of 2.70 m and is rotatable about an axis at A. The bar weighs 25 kg and is kept in equilibrium by a force F which has its point of attack in B. is 45 degrees. How big is the force F?
(1/1/0)
Saved!
25 * 9.82 = 245.5 N
Number of words: 6
5) A trolley rolls at a constant speed to the right. On the cart is an upward cannon that suddenly shoots a bullet. The carriage continues to the right with the same speed as before. Where does the bullet end up when it falls? For a detailed reasoning.
(1/1/1)
Number of words: 0
6) A river is 200 m wide. The water in the river flows at a speed of 2.5 m / s. A motorboat steers across the river at its maximum speed, which in stagnant water is 5.0 m / s. The boat is constantly heading perpendicular to the banks of the river. Where does the motorboat land on the other shore?
(2/0/0)
Number of words: 0
7) A ball with a mass of 2.0 hg moves at a constant speed in a circular path. The radius of the track is 1.5 m and it takes the ball 3.0 seconds to move one turn. How big is the centripetal force?
(1/1/0)
Number of words: 0
8) A bullet moves at a constant speed. Can we then safely say that the resultant of the forces acting on the bullet is zero? Motivate and discuss your answer.
(0/1/1)
Number of words: 0
9) A conductor is located between the poles of a permanent magnet. The current in the conductor goes in the direction of the plane of the paper (away from the reader). How is the force acting on the leader directed?
(1/0/0)
a) To the right of the figure
b) To the left in the figure
c) Downwards in the figure
d) Upwards in the figure
10) Protons enter horizontally from the left between two large metal plates at a speed v = 0.80 Mm / s. The plates are connected to a voltage source with the pole voltage U. Between the plates there is a homogeneous magnetic field with a flux density of 38 mT directed perpendicular to the plane of the paper. The distance between the plates is 1.5 cm. They want the protons to continue with unchanged direction and speed between the plates. Which of the plates should be connected to the positive pole of the voltage source and how large should the voltage U be?
(0/2/0)
Number of words: 0
11) The magnetic flux Φ through a 700-speed coil decreases linearly with time according to the diagram below. Calculate the voltage across the coil at time t = 1.0 ms.
12) The current in a coil with an inductance of 35 mH has a growth rate of 6.2 A / s at a given moment. What is the instantaneous value of the ems induced in the coil?
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16.Fox News recently reported the results of a public opinion poll on supporting Trump that asked:
“Since he became the president,
...
Since he became the president, did President Trump act with the transparency and the integrity
that you expect from a president?” 675 voters responded the poll and 351 responded “YES.”
Assume that 40% of the U.S. population supports Trump.
a. Define a binary random variable, Y, for supporting Trump (Y=1) vs. not (Y=0).
Calculate the population mean (????????) and variance (????????
2
) for supporting Trump.
b. Calculate the sample mean ????̅ and the sample standard deviation of ????̅ (????????̅ ) for the poll.
c. Calculate the standard error of ????̅ and construct a 95% confidence interval from the
poll using ????̅ and its sample standard error.
d. Conduct a two-sided hypothesis test at 5% significance level to determine whether
40% of the U.S. population supports Trump. State the null and the alternative
hypotheses, calculate the test statistics and the associated p-value, and conclude. Is
the Fox News survey reliable? Why? Why Not?
e. Suppose that you wanted to design a survey that had a margin of error of at most 1%.
That is: the difference between the upper bound and the lower bound of the
confidence interval should be a maximum of 2 percentage points. For example, for
????̅ = 0.52 you are aiming for the 95 % CI to be [0.51 0.53].
How large should n be if the survey uses simple random sampling?
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18.Suppose you measure a block’s weight by hanging it from a spring scale. You find that it
weighs 34.0 N
...
34.0 N when it’s not in the water. When it’s submerged in water (the density of water is
1.00 x 103 kg/m3) the scale now reads 27.0 N. (a) What is the density of the block? (b) If you
suspended another object from the block that has a density of 3.20 x 103 kg/m3, with both objects
submerged, what would the object's mass need to be for the scale to once again read 34.0 N?
Note: Part (a) is worth 7 points, and part (b) is worth 8 points.
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20.Twenty students are asked to select an integer between 1 and 10. Eight choose either 4, 5 or 6.
a If
...
f the students make their choices independently and each is as likely to pick one integer
as any other, what is the probability that 8 or more will select 4,5 or 6?
b Having observed eight students who selected 4, 5, or 6, what conclusion do you draw based
on your answer to part (a)?A missile protection system consists of n radar sets operating independently, each with a
probability of .9 of detecting a missile entering a zone that is covered by all of the units.
a If n = 5 and a missile enters the zone, what is the probability that exactly four sets detect
the missile? At least one set?
b How large must n be if we require that the probability of detecting a missile that enters the
zone be .999?
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23.A mathematician diagnosed with schizophrenia is fooling himself by playing
with a list L containing n distinct integers in just his
...
ng n distinct integers in just his thoughts.
He plays turns on the list. In each turn he does the following–
He takes a number (in its index’s order ) and swap it with any number in
the list including itself i.e. if it swap it with itself it doesn’t move at all (The
selection of the number is completely random).
He does the same for all the elements in their index’s order in that turn.
If initially the list was unsorted, such that, no element was in sorted position,
then find the probability that the list is sorted after m such turns.
Note : Take the assumption that if an element is not in its sorted
position then it can be in any other n − 1 positions equally likely.
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25.Use g = 9.8 m/s2.
The diagram below is a top-down view of two children pulling a 11.8-kg sled along the
...
ng the snow. The first child exerts a force of F1 = 11 N at an angle θ1 = 45° counterclockwise from the positive x direction. The second child exerts a force of F2 = 6 N at an angle θ2 = 30° clockwise from the positive x direction.
Find the magnitude (in N) and direction of the friction force acting on the sled if it moves with constant velocity.
magnitude
direction (counterclockwise from the +x-axis)
What is the coefficient of kinetic friction between the sled and the ground?
What is the magnitude of the acceleration (in m/s2) of the sled if F1 is doubled and F2 is halved in magnitude?
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28.hello can you please help to solve this system of equations k == (Sqrt[y^2 - 2 y^3 - y^4 +
...
+ Sqrt[2 - 2 y] -
k)/((y + 1) Sqrt[1 - y^2]),
Sqrt[2]/2/m == k/(k - Sqrt[2 - 2 y]), n ==
Sqrt[2 - 2 Sqrt[1 - m^2]], z == Sqrt[2 - 2 y]/f ==
Sqrt[(zn)^2 - 2 + 2 y]/
Sqrt[n^2 - f^2], t == (Sqrt[g^2 - 2 g^3 - g^4 + 2 g + 1] +
Sqrt[2 - 2 g] - t)/((g + 1) Sqrt[1 - g^2]),
Sqrt[2]/2/h == t/(t - Sqrt[2 - 2 g]), q ==
Sqrt[2 - 2 Sqrt[1 - h^2]], l == Sqrt[2 - 2 g]/p ==
Sqrt[(lq)^2 - 2 + 2 g]/
Sqrt[q^2 - p^2], (z + 1) x == (l + 1) 2 x == (y + 1) Sqrt[1 - y^2]/
Sqrt[2] == Pi/4, q == m and determine true it or false thank you
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35.We analyzed a program which was supposedly used for cracking some cryptographic algorithms.During the investigations we determined that the program
...
e investigations we determined that the program input size can be varied in a wide range and for N-bit input the program result is also always N – Bit long. Additionally we found that the program working time depends significantly on input length N, especially when N is greather than 10- 15 . Our test also revealed, that the program working time depends only on input length ,not the input itself.
During our tests, we fixed the following working times (with an accuracy of one hundredth of a second)
N = 2 – 16.38 seconds
N = 5 – 16.38 seconds
N = 10 – 16.44 seconds
N = 15 – 18.39 seconds
N = 20 – 1 minute 4.22 seconds
We also planned to test the program for N = 25 and N = 30, but for both cases the program didn’t finish within half and hour was forced to terminate it. Finally, we decided for N = 30 to not terminate the program,but to wait a little bit longer.The result was 18 hours 16 minutes 14.62 seconds . We repeated the test for N = 30 and it gave us exactly the same result, more than 18 hours.
Tasks:
a) Find the program working times for the following three cases N = 25, N = 40 and N = 50.
b) Explain your result and solution process.
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42.Draw an Epicycloid graph based on the given integer values of s, a, b, and n, where b cannot be
...
onnect a line between every two consecutive points (xi, yi) and (xi+1, yi+1), where 0 <= i <= n.
xi = s * ((a + b) * cos (i * PI) - b * cos ((a + b) / b * i * PI))
yi = s * ((a + b) * sin (i * PI) - b * sin ((a + b) / b * i * PI))
Verify with s = 10, a = 19, b = 5, n = 1000 to get this displayed result.
Note that the sin and cos trigonometry functions accept a radiant value not angle. For example, 30 degree should be replaced with PI/180*30 instead. Moreover, the divisions inside the functions need to be kept in double not int precision in order to render a correct result.
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44.Write a shell script, reddita.sh, to download the subreddit NetflixBestOf and only print the
complete data object as present inside each
...
te data object as present inside each element of the array children . The output will be
series of lines as follows:
"data": {...}
"data": {...}
The contents between the curly braces will vary from one data object to another, and the
subfields can be objects themselves (i.e., the subfields may have their values surrounded by
curly braces). At the time of this writing, 26 such objects printed.
It is critical to keep in mind that the order of the fields within the data objects is not
important. The closest this can be described in C is as follows:
struct data {
char c;
long n;
};
The application code mustn't rely on the fact that field c was defined before the field n . In
other words, a well written C application would work perfectly, without any code changes,
even if the structure was redefined as follows:
struct data {
long n;
char c;
};
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