Physics

How much heat, in joules, is transferred into a system when its internal energy decreases by 125 J while it was performing 30. 5 J of work
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(b)(iii) Explain in terms of photons what effect, if any, increasing theintensity of this radiation would have on the number of electronsejected per second, and on their maximum kinetic energy.[3]In 1902, Einstein's equation: Exmax hf- was revolutionary because it gavestrong evidence for light behaving as particles. Explain why this theory wascontroversial in 1902, but is now accepted as standard pre-university physics.[4]
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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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Jake wants to prove the theorem that says that the measure of the quadrilateral's opposite angles add to 180
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Compare and contrast compounds and mixtures (select all that are true):Compounds are pure substances, but mixtures are not. When two elements bond together into a compound they have new properties. o When two substances are mixed together in a mixture, they keep their individual properties. Compounds are physically combined. O Mixtures are chemically combinded.
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What is wind ? What type of energy is possessed by wind ? (b) Explain how, wind energy can be used to generate electricity. Illustrate your answer with the help of a labelled diagram. (c) State two advantages of using wind energy for generating electricity. (d) Mention two limitations of wind energy for generating electricity
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Determine the force acting downwards on a mass of 1500 g suspended on a string. (14. 72 N)
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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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What evidence supports the idea that the universe is expanding in alldirections?O A. Cosmic background radiationOB. Nuclear fusion in starsO C. NucleosynthesisD. Redshift
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Which model of the universe is the most widely accepted, and what does itpredict?A. An open universe, in which the universe never stops expandingB. A flat universe, in which the universe stops expanding but does notcontractC. A closed universe, in which the universe stops expanding but doesnot contractOD. A closed universe, in which the universe never stops expanding
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A team of astronauts is on a mission to land on and explore a large asteroid. In addition to collecting samples and performing experiments, one of their tasks is to demonstrate the concept of the escape speed by throwing rocks straight up at various initial speeds. With what minimum initial speed esc will the rocks need to be thrown in order for them never to "fall" back to the asteroid? Assume that the asteroid is approximately spherical, with an average density =2.02106 g/m3 and volume =1.711012 m3.Recall that the universal gravitational constant is =6.671011 Nm2/kg2.
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If a rocket takes off from earth with a certain force what must be true about earth
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A ball of mass 4 kg travelling at 10 m/s makes an elastic head-on collision with another ball of mass 1 kg which is at rest. After the collision, the speed of the lighter ball is*zeroless than 10 m/sequal to 10 m/sgreater than 10 m/s .
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How old was isaac newton when in 1666 he formulated the theory of universal gravity?
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Marshall paddled his kayak 919meters across a lake at a constant velocity. He moved that distance in 10. 0minutes. What was his velocity?
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Marci drops a ball off the top of the Empire state building. How fast is the ball traveling after 4 seconds? (assuming there is no air)
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What is the approximate electrostatic force between two protons each having a charge of +1. 6 x 10-19 C separated by a distance of 1. 0 106 meter?A)2. 3 1016 N and repulsiveB)2. 3 1016 N and attractiveC)9. 0 1021 N and repulsiveD)9. 0 1021 N and attractive
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how friction oppse motion
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A 50. 0 kg ice skater is standing at rest on the ice holding a 2. 0 kg medicine ball. She throws the medicine ball to the right with a horizontal velocity of 1. 8 m/s. What is the velocity of the skater after she throws the ball?
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A car travels at 54 km/h for first 20 s, 36 km/h for next 30 s and finally 18 km/h for next 10 s. Find its average speed.
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A 2.0 x 103 kg car is pulled 345 m up a hill that makes an angle of 15 with the horizontal.a. What is the potential energy of the car at the top of the hill?b. If the car rolls down the hill, what will its speed be if we neglect friction?
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A simple circuit has a 20 resistor and carries 0. 3 A. What is the voltage of the power source?
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Como puedo saber la carga de una partcula en un campo magntico
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Sonography uses infrasonic waves to create images of objects found inside other objects.TrueFalse
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