Physics

Acetone, a component of some types of fingernail polish, has a boiling point of 56C. What is its boiling point in units of kelvin? Report your answer to the correct number of significant figures.
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Charge 9 1018 C is on the y axis a distance 5 m from the origin and charge 9 1018 C is on the x axis a distance d from the origin. What is the value of d for which the x component of the force on 9 1018 C is the greatest? The Coulomb constant is 8.98755 109 N m2 /C 2 .
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A physics demo launches a ball horizontally while dropping a second ball vertically at exactly the same time. Trajectories of two balls. The balls are initially placed at the same height above the ground. The first ball moves vertically downward, and hits the ground directly below the initial point. The second ball is launched horizontally, and follows a parabolic trajectory until it hits the ground at some horizontal distance from the initial point. Which ball hits the ground first?
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A woman exerts a total force of 7 pounds in a horizontal direction on a box as she pushes it up a ramp that is 10 feet long and inclined at an angle of 30 degrees above the horizontal. Find the work done on the box.
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A 124-kg balloon carrying a 22-kg basket is descending with a constant downward velocity of 20.0 m/s. A 1.0-kg stone is thrown from the basket with an initial velocity of 15.0 m/s perpendicular to the path of the descending balloon, as measured relative to a person at rest in the basket. That person sees the stone hit the ground 5.00 s after it was thrown. Assume that the balloon continues its downward descent with the same constant speed of 20.0 m/s. (a) How high is the balloon when the rock is thrown? (b) How high is the balloon when the rock hits the ground? (c) At the instant the rock hits the ground, how far is it from the basket? (d) Just before the rock hits the ground, find its horizontal and vertical velocity components as measured by an observer (i) at rest in the basket and (ii) at rest on the ground.
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100 ml of water is initially at 20C. 30,000 J of heat is added to the water. What is temperature change for the water?
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Millikan is doing his oil drop experiment. He has a droplet with radius 1.6 m suspended motionless in a uniform electric field of 46 N/C. The density of the oil is 0.085 g/cm3 . Calculate for Millikan the charge on the droplet. Is quantization of charge obeyed within the precision of this experiment?
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If the potential due to a point charge is 490 V at a distance of 10 m, what are the sign and magnitude of the charge?
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Explain why a law is accepted as fact, but a theory is not
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Which statement is the best interpretation of the ray diagram shown below?
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A cathode-ray tube (CRT) is an evacuated glass tube. Electrons are produced at one end, usually by the heating of a metal. After being focused electromagnetically into a beam, they are accelerated through a potential difference, called the accelerating potential. The electrons then strike a coated screen, where they transfer their energy to the coating through collisions, causing it to glow. CRTs are found in oscilloscopes and computer monitors, as well as in earlier versions of television screens.If the accelerating potential is 95.0 V, how fast will the electrons be moving when they hit the screen?
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Particle physicists use particle track detectors to determine the lifetimeof short-lived particles. A muon has a mean lifetime of 2.2sand makes a track 9.5 cm long before decayinginto an electron and two neutrinos. What was the speed of the muon?
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If a mass of 0.5 kg is displaced by 30 cm using a spring with a spring constant of 2 N/m, find the following:a) The angular frequencyb) The period of oscillationc) The position at t = 2 secondsd) The velocity at t = 2 secondse) The acceleration at t = 2 seconds
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A total charge of 6.3 x 10-8 C is placed on a 2.7 cm radius isolated conducting sphere. The surface charge density is: A. 2.55 x 10-4 C/m3 Explain B. 8.64 x 10-5 C/m2 C. 2.75 x 10-5 C/m2 D. 6.88 x 10-6 C/m2 E. 7.43 x 10-7 C/m
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A charged paint is spread in a very thin uniform layer over the surface of a plastic sphere of diameter 18.0 cm , giving it a charge of-29.0 C .A Find the electric field just inside the paint layer.Express your answer with the appropriate units. Enter positive value if the field is directed radially inward and negative value if the field is directed radially outward.B Find the electric field just outside the paint layer.Express your answer with the appropriate units. Enter positive value if the field is directed radially inward and negative value if the field is directed radially outwardC Find the electric field 6.00cm outside the surface of the paint layer.Express your answer with the appropriate units. Enter positive value if the field is directed radially inward and negative value if the field is directed radially outward.
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How and why does a day measured with respect to the Sun differ from a day measured with respect to the stars?
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A potential difference exists between the inner and outer surfaces of the membrane of a cell. The inner surface is negative relative to the outer surface. If 1.35 10 20 J 1.351020 J of work is required to eject a positive sodium ion (Na + ) (Na+) from the interior of the cell, what is the magnitude of the potential difference between the inner and outer surfaces of the cell?
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Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?-Dehydration reactions can occur only after hydrolysis.-Dehydration reactions ionize water molecules and add hydroxyl groups to polymers; hydrolysis reactions release hydroxyl groups from polymers.- Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers.-Hydrolysis creates monomers, and dehydration reactions break down polymers.-Dehydration reactions eliminate water from lipid membranes, and hydrolysis makes lipid membranes water permeable.
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Two cars collide at an icy intersection and stick together afterward. The first car has a mass of 1050 kg and was approaching at 6.00 m/s due south. The second car has a mass of 750 kg and was approaching at 25.0 m/s due west.
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Two siblings are in a funny mood and push each other away with a force of 20 N. If sibling 1 has a mass of 50 kg and sibling 2 a mass of 60 kg, what will be the ratio between their respective accelerations (sibling 1 : sibling 2)? (2 significant figures)
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What do the lines making a circle around the low-pressure area indicate? areas of equal altitude areas of equal pressure a stationary front an occluded front
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A 5 kg ball approaches a wall at a speed of 4 m/s. It then bounces off the wall in the opposite direction at the same speed. What is the magnitude of the average force exerted on the ball if it is in contact with the wall for 0.1 s?
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A car moves along a horizontal road with constant velocity v0 = v0xi until it encounters a smooth inclined hill, which it climbs with constant velocity v1 = v1xi + v1yj as indicated in the figure. The period of time during which the car changes its velocity is t.
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Estimate how much farther a person can jump on the Moon as compared to Earth if the take offspeed and angle are the same? The acceleration due to gravity on the moon is one-sixth what itis on Earth.
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