Master Physics with Fun Quizzes & Brain Teasers!

At the gym, a man pulls a bar on a machine that works the muscles of the upper back. It takes him 0. 5 seconds to raise 30kilograms of weights a vertical distance of 0. 5 meters. Which of these exerts the same power output? (Estimate g as 10 m/s2. )A) lifting 25 kilograms a distance of 2. 4 meters in 2. 0 secondsB) lifting 45 kilograms a distance of 2. 4 meters in 3. 0 secondsC) leg pressing 45 kilograms a distance of 0. 5 meters in 0. 5 seconds. D) bench pressing 30 ligrograms a distance of 0. 5 meter in 1. 5 seconds. Pleaseeeeeee help me
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An electron traveling with speed v around a circle of radius r is equivalent to a current of:evr/2ev/rev/2r2er/v2ev/r
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A proton moving eastward with a velocity of 5. 0 km/s enters a magnetic field of 0. 20 T pointing northward. What are the magnitude and direction of the force that the magnetic field exerts on the proton
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How much time does it take light from a flash camerato reach a subject 6.0 meters across a room?
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Particles q1, 92, and q3 are in a straight line.particles q1 = -1.60 x 10-19 c, 92 = +1.60 x 10-19 c,and q3 = -1.60 x 10-19 c. particles 91 and q2 areseparated by 0.001 m. particles q2 and q3 areseparated by 0.001 m. what is the net force on 92?remember: negative forces (-f) will point leftpositive forces (+f) will point right-1.60 x 10-19 c+1.60 x 10-19-1.60 x 10-19 c91+ 92930.001 m0.001 m
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A flashlight can be made that is powered by the induced current from a magnet moving through a coil of wire. The coil and magnet are inside a plastic tube that can be shaken causing the magnet to move back and forth through the coil. Assume the magnet has a maximum field strength of 0. 05 T. Make reasonable assumptions and specify the size of the coil and the number of turns necessary to light a standard 1-watt, 3-V flashlight bulb
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Instruction: Answer all questions Time: 1. 5hrs An electron is placed in a uniform electric field with field strength of 150kvm Calculate the duration for it to travel 30mm from its stationary Position Give an explanation for your answer.
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An engine is received that hunts and surges at top no-load speed only. to determine whether the carburetor or the governor system is causing the symptom, a specific troubleshooting process can be followed. technician a says that to separate the governor system from the carburetor, simply hold the throttle plate still and see if the engine continues to hunt & surge. technician b says that hunting and surging is caused exclusively by a lean mixture in the carburetor. which technician is correct? technician a technician b both technicians a and b neither technicians a nor b
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The caloris basin on mercury covers a large region of the planet, but few craters have formed on top of it. from this we conclude that the :_________.i. caloris basin was formed by a volcano. ii. erosion destroyed the smaller craters that formed on the basin. only very large impactors hit mercury's surface in the past. iii. the caloris basin formed toward the end of the solar system's period of heavy bombardment. iv. mercury's atmosphere prevented smaller objects from hitting the surface.
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6 If an object goes from 30 to 25 degrees Celcius, what is the change in Temperature?7How much energy is needed to heat 35 g of gold from 10 to 50 Degrees celcius?1294018060. 358Specific heat is. a
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Your lawn is twice as large as your neighbors lawn. You both start cutting your lawn with the same model, self-propelled lawn mower (requiring the same force) beginning at 9:00am on a Saturday morning. You finish cutting your lawn at 11:00 am. What time will your neighbor finish cutting her lawn if you are equally powerful?
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How far do you have to lift a 10kg bag of salt to do 250j of work?
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An inflated car tyre is considered to have a constant volume, regardless of any changes in temperatureor pressure. Use the kinetic theory of gases to answer following. a) How does the air in the tyre exert pressure on the walls of the tyre?b) Why is the pressure the same at all points on the inside wall of a tyre?c) What happens to the pressure on the inside walls of the tyre if the temperature of the air increases? Explain your answer. d) More air is pumped into the tyre whilst the temperature is kept constant until there are twice as many molecules as before. Explain why you would expect the pressure to be doubled
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A simple pendulum and a spring-mass pendulum both have identical frequencies. How can you change them so that they will still have identical frequencies?
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Physics questiontwo concrete spans of a 180 m long bridge are placed end to end so that no room is allowed for expansion. if the temperature increases by 20c, what is the height to which the spans rise when they buckle? assume the thermal coefficient of expansion is 1.2 10^5(c)^1. answer in units of m.
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His is an artist's model of the solar system. The scale bar in the drawing represents AU s. One AU is the distance rom the Sun to the Earth, which is about 93 million miles or 150 million kilometers. Is this an accurate scale model? Explain A) No. If Earth is 1 AU away from the Sun, Neptune should be about 30 AU'S away. It is not B) Yes, it is an accurate scale model showing the relative distances of each planet from the Sun. C Yes the drawing is to scale. The artist shows how the diameters compare as well as the distances from the Sun in AU's. Neither the distances from the Sun or the size of the planets are drawn to scale. Both are too small according to actual distances and diameters,
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Researchers are trying to use radiocarbon dating to determine when the wooden buildings at an archaeological site were constructed. They know that trees in the area would have been cut down for the construction, and that when the trees died, they would have a ratio of carbon-14 to carbon-12 of about one part per trillion (1 ppt). The half-life for the decay of carbon-14 is 5,730 years, and they discover the ratio of carbon-14 to carbon-12 to be about 0. 125 parts per trillion (ppt). What is the age of the buildings at the site? *716. 25 years5,730 years17,190 years0. 125 billion years
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1. how much is the increase in temperature from 1880 to 2010?2. what happened to the amount of carbon dioxide from 1880 to 2010?3. what is the relationship between the amount of carbon dioxide and global temperature?4. when was temperature at its highest and at its lowest?please help neep asap....
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If the charge of each two particles is doubled and the seperation between them is also doubled. the force between the two particles is?
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Each airport has a runway that is about 500 m long.when it lands, the speed of the aeroplane is 40 m/s.explain why the airline should not use an aeroplane that has more mass andneeds a higher speed for landing.
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Roger is a forensic investigator. His examination of a dead body reveals that the body is completely limp. Which state is the body in?A. Rigor MorrisB. Algor MorrisC. Pallor MorrisD. Primary Flaccidity
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A honey bee's wings beat at 230 beatsper second. If the speed of sound in airis 340 m/s, what is the wavelength of thesound wave?1 pt: knowns/unknown1 pt: write the equation1 pt: solve1 pt: correct answer (you can round toone decimal place)please answer right away
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Which list shows the correct order of processes that occur before and during ovulation?egg released from ovary Right arrow. Hormones send signal Right arrow. Egg travels to fallopian tubeegg travels to fallopian tube Right arrow. Egg is released from ovary Right arrow. Hormones send signalhormones send signal Right arrow. Egg travels to fallopian tube Right arrow. Egg released from ovaryhormones send signal Right arrow. Egg released from ovary Right arrow. Egg travels to fallopian tube
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How long does it take to shut down a nuclear reactor?.
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