A rope of negligible mass is stretched horizontally between two supports that are 2.81 m apart. When an object of weight 4190 N is hung at the center of the rope, the rope is observed to sag by 39.6 cm. What is the tension in the rope?
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A = 3, B = 9, C = 18. A (1.25+A) kg bowling ball is hung on a (2.50+B) m long rope. It is then pulled back until the rope makes an angle of (12.0+C) degrees with the vertical and released. Find the speed of the ball is at the lowest point. Give your answer in m/s and with 3 significant figures.
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To what height would a 3.0 kg object have to be raised such that its gravitational potential energy would equal the kinetic energy it would possess if it were moving at 3.0 m/s?
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1 Why is it cooler to wear a white shirt than a black shirt on a hot, sunny day?
2 On a hot day in your hot kitchen, you decide to work with the refrigerator door open in an attempt to have the refrigerator cool the room. Which of the following best describes the result of this decision? Explain your answer.
a It will cool the room very effectively
b It will cool the room, but inefficiently
c It will not change anything
d It will actually warm the room
3 Consider standing on a bathroom scale. How will the reading of the scale compare if you stand on one leg instead of two?
a It will show less
b It will show more
c It will show the same
4 Consider standing on a bathroom scale. What does a bathroom scale show?
a Mass
b Density
c Force
d Pressure
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SO what is the difference between heat and temperature? When you go about your everyday life which one do you concern yourself with more?
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The hunt for Red October is on! (Remember the 1990 Sean Connery
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why isn't it accurate to say static friction is the
force that keeps objects from moving? describe a counter example
like a box on a table
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Topic: Magnetism and electromagnetic induction, faraday's law, lenz's law
Question: A magnet is held a little above the top of a coil. It is then dropped into and through the loop, north side facing down, and caught as it exits the loop. Assuming the magnet never touched the loop (zero friction), would its velocity after falling through the loop be greater, smaller, or the same as if it had been dropped freely (not through the loop)? Explain your answer using force concepts and using energy concepts.
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Draw a labelled sketch showing how the eye works and which parts of the eye see variations of contrast, color and detail (include rods and cones in your sketch). What does the “blind spot” mean and where is it in the eye? Does the eye see an upright or an inverted image? How does the lens of the eye work? Is the lens static?
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Consider an equilateral triangle with sides measuring 1.0 m in length. At each point of the triangle is a +2.0 ?C charge. Calculate the Coulomb force on each charge. Recall that forces are vectors and thus your answer will require a magnitude and direction for each of the three forces.
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A mischievous young man riding a ferris wheel decides to release a beanbag as he passes the top point in the ride; at this point in the ride, the young man is traveling due West. The ferris wheel has a radius of 3.29 m and goes around once every 1.17 minutes \ . The bottom of the wheel is 1.11 m off the ground, so that the release point of the bag will be 7.69 m off the ground.
A)What is the velocity of the bean bag just before it is released by the mischievous young man? Give magnitude and direction. Give the direction as an angle in degrees measured counterclockwise from due East, when looking North.
B)What is the acceleration of the bean bag just before it is released by the mischievous young man? Give magnitude and direction. Give the direction as an angle in degrees measured counterclockwise from due East, when looking North.
C)For how much time is the bean bag in the air?
D)The young man finds that the bag does not land directly under the point of release. How far does the bag travel horizontally as it is falling?
It would help if you explain too thanks
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what is the between atoms and molecules? how do compounds and elements differ?
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A new type of 38.0 W lamp is designed to produce the same illumination as a conventional 53.0 W lamp. How much energy does this lamp save during 370.0 h of use? Answer in units of J.
If electrical energy costs $0.080/kW·h, how much money is saved in 370.0 h? Answer in units of $.
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In Fig. 8.3, a bullet of mass 0.01 kg moving horizontally strikes a block of wood of mass 1.5 kg which is suspended as a pendulum. The bullet lodges in the wood, and together they swing upward a distance of 0.40 m. What was the velocity of the bullet just before it struck the wooden block? The length of the string is 2 meters.
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A 100 cm^3 box contains helium at a pressure of 1.60 atm and a temperature of 120 ∘C. It is placed in thermal contact with a 190 cm^3 box containing argon at a pressure of 4.20 atm and a temperature of 390 ∘C.
What is the initial thermal energy of each gas?
What is the final thermal energy of each gas?
How much heat energy is transferred?
What is the final temperature?
What is the final pressure in each box?
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