Master Physics with Fun Quizzes & Brain Teasers!

Question 14 of 301 PointWhich of the following ideas was proposed by the ancient Greeks about 2500years ago?O A. Atoms consist of positive and negative charges.O B. Atoms are indivisible units of matter.OC. All atoms are alike.O D. Atoms are composed of protons, neutrons, and electrons.SUBMIT
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Culture influence learning styles?
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why do you think the moon appears to change shape as it revolves around the earth?
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if the moon did not revolve around the sun, would we still see moon phases?
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An electron moves at a speed of 1.0 x 104 m/s in a circular path of radius 2 cm inside a solenoid. The magnetic field of the solenoid is perpendicular to the plane of the electrons path. Calculate (a) the strength of the magnetic field inside the solenoid and (b) the current in the solenoid if it has 25 turns per centimeter.
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Object A has a charge q on it, object B has a charge q on it, and Object C has a charge 2q on it. These charges are arranged, one each, at the vertices of an equilateral triangle. Which charge has the greatest magnitude electric force on it?a. Ab. Bc. Cd. All have equal magnitude forces on them.
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The motion of spinning a hula hoop around one's hips can be modeled as a hoop rotating around an axis not through the center, but offset from the center by an amount h, where h is less than R, the radius of the hoop. Suppose Maria spins a hula hoop with a mass of 0.73 kg and a radius of 0.60 m around her waist. The rotation axis is perpendicular to the plane of the hoop, but approximately 0.38 m from the center of the hoop.(a) What is the rotational inertia of the hoop in this case? ________ kg m^2 (b) If the hula hoop is rotating with an angular speed of 14.1 rad/s, what is its rotational kinetic energy?
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Ocean waves of wavelength 30m are moving directly toward a concrete barrier wall at 4.8m/s . The waves reflect from the wall, and the incoming and reflected waves overlap to make a lovely standing wave with an antinode at the wall. (Such waves are a common occurrence in certain places.) A kayaker is bobbing up and down with the water at the first antinode out from the wall.A) How far from the wall is she?B) What is the period of her up and down motion?
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Jessica stretches her arms out 0.60 m from the center of her body while holding a 2.0 kg mass in each hand. She then spins around on an ice rink at 1.1 m/s. a. What is the combined angular momentum of the masses? b. If she pulls her arms into 0.15 m, what is her new linear speed?I'm really confused ab the explanations behind this. help, please
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The volume of 1 kg of helium in a pistoncylinder device is initially 5 m3. Now helium is compressed to 2 m3 while its pressure is maintained constant at 174 kPa. Determine the initial and final temperatures of helium as well as the work required to compress it, in kJ. The gas constant of helium is given to be R = 2.0769 kJ/kgK. (Round the temperatures to one decimal place and the work required to the nearest whole number.)
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The estimated distance of the earth from the sun is 149000000km. The speed of the light is 300000km/s. What is the time taken for the light to travel from the sun to the earth
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A ball of mass 2.00-kg is dropped from a height of 1.5 m (from the ground) onto a massless spring (the spring has an equilibrium length of 0.50 m). The ball compresses the spring by an amount of 0.20 m by the time it comes to a stop. Calculate the spring constant of the spring.
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Provided the diameter of the fire hose is 7.0 cm, and the water running through the hose flows at 420 L/min, how much force does she need to hold the nozzle, if its diameter is 0.75 cm?
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An empty parallel plate capacitor is connected between the terminals of a 10.1-V battery and charges up. The capacitor is then disconnected from the battery, and the spacing between the capacitor plates is doubled. As a result of this change, what is the new voltage between the plates of the capacitor
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The potential energy of a pair of hydrogen atoms separated by a large distance x is given by U(x)=C6/x6, where C6 is a positive constant. Part A What is the force that one atom exerts on the other? Express your answer in terms of C6 and x. Fx = nothing Request Answer Part B Is this force attractive or repulsive? Is this force attractive or repulsive? attractive repulsive
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Using all three of Newton's laws of motion, carefully describe the motion of a baseball beginning when the ball is resting in the pitcher's glove as he stands on the mound until the ball is hit by the batter (assume the ball is hit). Ignore what kind of pitch is thrown and air resistance. The answer should focus on the forces and motion of the ball (not the players), and should include which of Newton's laws each motion/force follows. = = . O Words
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Which property of argon is used in light bulbs?
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A hawk is flying horizontally at 18.0 m/s in a straight line, 230 m above the ground. A mouse it has been carrying struggles free from its grasp. The hawk continues on its path at the same speed for 2.00 s before attempting to retrieve its prey. To accomplish the retrieval, it dives in a straight line at constant speed and recaptures the mouse 3.00 m above the ground. (a) Assuming no air resistance, find the diving speed (magnitude of the total velocity vector) of the hawk. (b) What angle did the hawk make with the horizontal during its descent? (c) For how long did the mouse "enjoy" free fall?
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John drives his car 120 miles east in 2 hours, 90 miles east in 1.5 hours, then he stops at the gas station for half an hour. He soon realizes that he has to go back 8 miles west which takes him one hour to reach his final destination. Calculate his average velocity during the entire time.
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hree identical resistors are connected in series. When a certain potential difference is applied across the combination, the total power dissipated is 45.0 W. What power would be dissipated if the three resistors were connected in parallel across the same potential difference
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A rescue plane flies horizontally at a constant speed searching for a disabled boat. When the plane is directly above the boat, the boat's crew blows a loud horn. By the time the plane's sound detector receives the horn's sound, the plane has traveled a distance equal to one-fourth its altitude above the ocean. Assuming it takes the sound 2.02 s to reach the plane, and taking the speed of sound to be 343 m/s, determine the following.(a) The speed of the plane. (Take the speed of sound to be 343 m/s.) ___m/s (b) What is its altitude? ___m
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The following four waves are sent along strings with the samelinear densities (x is in meters and t is in seconds). Rank the waves according to (a) their wave speed and (b) the tension in the strings along which they travel, greatest first:1 $$y_1 = (3 mm) sin(x - 3t)$$, (1) $$y_2 = (6 mm) sin(2x - t)$$, (3) $$y_3 = (1 mm) sin(4x - t)$$, (4) $$y_4 = (2 mm) sin(x - 2t)$$,
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For the following types radio waves infared radiation visible light ultraviolet radiation gamma radiation of electromagnetic radiation, how do the wavelength, frequency, and photon energy change as one goes from the top of the list to the bottom? Wavelength Frequency Photon Energy 1. Increases Decreases Increases 2. Increases Decreases Decreases 3. Decreases Decreases Increases 4. Increases Increases Increases 5. Decreases Increases Increases
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In testing an automobile tire for proper alignment, a technician marks a spot on the tire 0.220 m from the center. He then mounts the tire in a vertical plane and notes that the radius vector to the spot is at an angle of 30.0 with the horizontal. Starting from rest, the tire is spun rapidly with a constant angular acceleration of 1.90 rad/s2. (Assume the spot's position is initially positive, and assume the angular acceleration is in the positive direction).A) What is the angular speed of the wheel after 1.30 s?B) What is the tangential speed of the spot after 1.30 s?C) What is the magnitude of the total acceleration of the spot after 1.30 s?D) What is the angular position of the spot after 1.30 s?
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