What is the average power in watts he expends climbing the hill? A body is moving unidirectionally under the influence of a source of constant power. Questions I. a. lift heavy objects b. do less work in more time c. do more work in less time d. exert a larger force... How long does it take a vehicle with 40 horse power to achieve a speed of 25 m/s starting from rest? Work, energy and power are very subjective and insists students write accurate answers to questions posed to them. Persons A and B do the same job, but B takes longer. Which uses more power? P = W. A slurry handling system was evaluated and found to require an energy input (from the pump) of 340 J/kg. CIE IGCSE Physics exam revision with multiple choice questions & model answers for Energy, Work & Power. V. The car is parked far from the building, so he uses an extension cord 15.0 m long to plug the cleaner into a 12... What average mechanical power (in W) must a 61.5 kg mountain climber generate to climb to the summit of a hill of height 405 m in 46.0 min? The human brain consumes about 22 \ W of power under normal conditions, though more power may be required during exams. The leng... A 120 V power line is used to operate three devices in parallel with power ratings 100 W, 200 W, and 300 W. What is the minimum value of fuse that needs to be used to protect this circuit (in Amps)? unit of power is J/s or Js-1 (or watt W). Is it possible to solve for X? Energy resources Most of the energy we use is obtained from fossil fuels - coal, oil and natural gas. Which boy is more po... A 90\ \mathrm{kg} mover climbs a ladder to a height of 8\ \mathrm{m} in 32\ \mathrm{s}. “Power can be expressed as the product of force and velocity.” Answer: (Since rate of change of displacement is velocity). 2. 5 terawatts b. Long Answer Questions. A certain rain cloud at an altitude of 1.75 km contains 3.20 x 10^7 kg of water vapor. The average mass of skiers complete with equipment is 85 kg. A 607-kg elevator starts from rest and moves upward for 4.40 s with constant acceleration until it reaches its cruising speed, 1.73 m/s. Question 58: State S.I. A 1500 kg car accelerates uniformly from rest to a speed of 18 m/s in 4.59 s. \\ A) Find the work done by the net force on the car during this time interval. Calculate the torque. b) What average force did the engine exert? 4.You’re driving a snowmobile that accelerates from 10 m/s to 20 m/s over a time interval of 10.0 s. If you and the snowmobile together have a mass of 500 kg, how much power is used? With what velocity will it move? Take mechanical efficiency as eta m = 0.80. i. Extra Challenging Physics Questions The 20 physics questions given below are both interesting and highly challenging. b) It is maximal at maximal velocity. How long can one Snickers bar (280 Cal per bar) power the normally functi... a) What is the average useful power output of a person who does 6.00x10^6J of useful work in 8.00h? Services, Working Scholars® Bringing Tuition-Free College to the Community. How much energy did it take to produce the dam? Consider a fan located in a 2.5 ft \times 2.5 ft square duct. When its engines are developing their full power of 260,000 \ hp, the George Washington travels at its top speed of 35 knots... A circuit consists of five elements. Analogies exist between rotational and translational physical quantities. Alternating Current Important Questions for CBSE Class 12 Physics Introduction to Alternating Current. Paul and John have the same mass of 50 kg. Mark Scheme. They can be spun up slowly, then the wheel's energy can be released quickly to accomplish a task that demands high power. Once supplies of these fuels have been used up they cannot be replaced they are non-renewable. A truck of mass 2 tonnes moving at a speed of 25 m/s is brought to rest suddenly in 5 seconds. (g = 10 m/s^2 ). Derive an equation for power associated with torque. Q. How much power does a 63 kg athlete develop as he climbs a 5.2 m rope in 3.5 seconds? 30 seconds . About this quiz: All the questions on this quiz are based on information that can be found at Physics: Power. CREATE AN ACCOUNT Create Tests & Flashcards. Access the answers to hundreds of Power in physics questions that are explained in a way that's easy for you to understand. The heart may be regarded as an intermittent pump that forces about 70 cm cubed of blood into 1.0cm radius aorta about 75 times a minute. The following question is based on one of the core practicals / required practical activities on the GCSE Physics specification, which you should have carried out in class. I... A 1400 ohm resistor has 120 volts across it. A particle of mass 'm' moves along a circle of radius R with a normal acceleration varying with time as a = b t 2 where b is a constant. The total mass of the train is 875 g. Find the average power delivered to the train during the accelerat... You are testing a new car in a wind-tunnel for road and wind resistance. The rotor shaft would not fit into the searing. NEET Physics Work,Energy and Power questions & solutions with PDF and difficulty level AQA A level Physics Worksheets, exam style questions. If this motor is being used to lift a crate of mass 192 kg, how fast (i.e., at what speed) can it lift the crate? a. They are probably the first thing you learn in your Physics class. It faces a force of 400 N from air resistance. A meter stick is held vertically with one end on the floor and is then allowed to fall. unit of power is J/s or Js-1 (or watt W). In the International System of Units, the unit of power is the watt, equal to one joule per second. Consider a 2100-kg car cruising at constant speed of 70 km/h. A stone used to grind wheat into flour is turned through 11 revolutions by a constant force of 21.1 N applied to the rim of a 10.2-cm-radius shaft connected to the wheel. Can't find the question you're looking for? If your power output is 138 W, and the mass of the bucket and the water init is 4.00 Kg, with what speed can you raise the bucket? GENERAL PHYSICS On a windy day this wind turbine generates 2000 kW of electricity. Mark Scheme. Made by expert teachers. What is an expression for the average power delivered by the car's engine? The power delivered to the turbine is . (a) Calculate the work ( kJ ) done by th... How much work is done by an engine using 105 watts of power in 3.2 seconds? holt-physics-current-resisance-and-power-questions 1/2 Downloaded from web01.srv.a8se.com on December 18, 2020 by guest [MOBI] Holt Physics Current Resisance And Power Questions Eventually, you will extremely discover a new experience and endowment by spending more cash. A 1.10 x 10^3 kg car accelerates from rest for a time period of 5.0 sec. Math and Physics Expert. Upgrade to PLUS + for €35 to see all past questions. Get help with your Power in physics homework. The electric motor of a model train accelerates the train from rest to 0.755 m s in 19.5 ms. Explain with graphs the difference between work done by a constant force and by a variable force. a) person A b) person B c) they both did equal amounts of work Who is more "powerful"? One slice of pizza's energy content is 300 cal or 1260 KJ. It is maximal at approximately 2/3 maximal isometric force production. b) About the y axis? A constant power P is applied on a particle of mass m. Find kinetic energy, velocity and displacement of particle as function of time t. Determine how long an energy storage device can be used when it is known that for this type of system the output power is a polynomial function of time Power = a_o - bt^2, where a_o = 2.5(10^5)W an... A 2000 kg car, initially at rest, is accelerated along a horizontal roadway at 3 m/s2. 1.A 1,000-kg car accelerates from 88 m/s to 100 m/s in 30 s. How much power does that require? How long will it take a 230 W motor to lift a 335 kg piano to a sixth-story window 19.0 m above? Girl A takes 20 sec while B takes 50 sec to accomplish the task. If you push a lawn mover across a yard in 10 seconds, how does the work done compare with pushing it across the same yard in 20 seconds? Final question is ‘stretch and challenge’ - goes into the power-matching situation for internal resistance. What is the average power output of the elevator motor if the... A 70 kg man carrying a 10 kg suitcase climbing a ladder of 5 m in two minutes, power developed by the man is [{Blank}]. Calculate the number of kilo calories needed to climb 232 stair steps 116 steps per minute for 2 min. AQA A Level Physics revision resources. they are sending power P0 by transmission voltage V0 from substation A to B. Grab a pen and paper and try this Work, Energy and Power Quick Quiz! Tutorials, tips and advice on GCSE Physics coursework and exams for students, parents and teachers. It is measured by the product of the force and the distance moved in the direction of the force, i.e., W = F-S For example, in this question, it is unlikely t… How long does it take for the ice cube to melt? Escalator steps move with a constant speed of 0.6 m/s. 0 over a dam at the rate of 660 k g s and falls vertically 86 m before striking the turbine blades. Determine the average power generated by the force that accelerates the veh... A 685 kg elevator starts from rest and moves upward for 2.80 s with constant acceleration until it reaches its cruising speed, 1.71 m/s. 4 Min Quiz Image: refer to hsw About This Quiz. (b)... A Russian weightlifter in the 2000 Olympic games is able to lift a 250-kg mass a vertical distance of 2 m in 2 seconds. An adult generates 72 W of power as she pulls a sled forward across a flat snowy surface with a force of 80 N. The adult pulls with this force for 4.5 minutes. Power is the rate at which work is done. What is the useful output power of the hoist? a. In a stair case power lab, if you have the height of the steps, the time and the mass, how do you find the force and the power? Velocities at various points at the outlet are measured, and the average air flow velocity is determined to be 34 ft/s. Answer in units of W, The aerodynamic drag on an aeroplane is given by D=bv^2. Energy = 60 x 12 = 0.72 kW h. In this scenario, the power consumed during the whole day varies as one bulb is turned ON for only 12 hours, so we have to calculate average power, the object moves. A box that weighs 645 n is lifted a distance of 20.0 m straight up by a cable attached to a motor. (Answer in 2 significant figures, in J.) Calculate the work done in joules and the power in watts when an object weighing 100 kg is lifted 3 m in 10 sec at a constant speed. What is the average power required to bring the car to a final speed of 20 m/s? If her mass is 20.0 kg, what distance does she slide after Zak's push ends? The lifting force does work in raising the helicopter. What average power is required for a runner with a mass of 80 kg to reach a speed of 8.2 m/s during a time of 1.8 s? An engine moves a boat through the water at a constant speed of 15 \ m/s. b )the average... How much power is used by a 50 kg athlete in climbing a 10 m high ladder in 9.8 sec? An online interactive physics quiz for NY Regents Physics work, energy, and power The heart must do work to overcome frictional forces that resist the blood flow. How does the power for 10 seconds is comp... An ice cube is placed in a microwave oven. “Power can be expressed as the product of force and velocity.” Answer: (Since rate of change of displacement is velocity). A person pushes a 10 kg cart a distance of 20 meters by exerting a 60 Newton horizontal force. Tick onebox. If the height gain of each step was 0.2 m, and the man's mass was 55.... a. a) What is the net work done by F(x) on the object as it is displa... A small plane with a mass of 600 kg lifts off from the runway at a speed of 145 km/hr. Physics of Power Quiz. The frictional resistance force is 50 Newtons. If a student took a running start before starting to travel up stairs, the power calculated will be incorrect. How does the power for 10 seconds compare... A professor's little car can climb a hill in 10 s. The top of the hill is 30 m higher than the bottom, and the car s mass is 1,000 kg. Want to see ALL questions on this topic? Compute the power output in watt of a machine that lifts a 50 kg crate through a height of 20 cm in 1 minute. \\ A. A 40-kg girl climbs a vertical ladder at 0.5 m/s. Work, energy and power are very subjective and insists students write accurate answers to questions posed to them. Scroll To Start Quiz. What is your power output while doing so? 1 watt is equivalent to: A 1 joule per second B 1 ⁄ 10 newton per metre C 1 newton metre: 13. As we shall see, there are good reasons not to do this! (b) What is the sprinter's power output... State whether a cumulative frequency, relative frequency, relative percent, cumulative relative frequency, or cumulative percent is most appropriate for describing the following situations. a) What work must a diesel engine in an 18,000 kg truck do to increase its speed from 30 m/s to 40 m/s in 5.0 s? How much power does he exert? This quiz includes the topics on Work, Energy and Power. (in watts) (a) How much work is required to pull him 65 m up a 30 degrees slope (assumed frictionless) at a constant speed of 3.2 m/s? It takes 130 minutes for a middle-aged physics professor to ride his bicycle up the road to Alpe d'Huez in France. If a car delivers 76.2 hp of power, how much time will it take for the engine to do 5.78e5 J of work? How much power is involved in Joachim's run up the hill? What is the power of the forklift if it does this job in half the time? put your answer in scientific notation. The climb is made in 5.5 h starting at an elevation of 2800 m. Assuming the body is 16% efficient, what rate of energy input was required? It starts from the top, at rest. All other trademarks and copyrights are the property of their respective owners. Find a) what is the power of the hoist in kW. You’re riding a toboggan down an icy run to a frozen lake, and you accelerate the 80.0-kg combination of you and the toboggan from 1.0 m/s to 2.0 m/s in 2.0 s. How much power does that require? Calculate the power exerted by the brakes. If you run 11-minute miles, what is your average power output, in watts, during a 2-hour run? J of work to move it 15 m makes an angle of 1.5 degrees ( sr ) 60... Walking on a windy day this wind turbine generates 2000 kW of electricity and v_2 respectively of... Are based on the syllabus guidelines prescribed by MCI the influence of a turbine-generator System with a of. Average power must she supply defined as what to Science for Kids Physics of power operating on 120V pattern..., oil and natural gas... why do earth and electrons rotate paper and try this work, and. Measuring power is 70 kW and the number of engine rolls is 3310 rpm (... The auto approaches a hill the driver shifts from high gear to low gear water over! 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