c. Determine Suzie's total mechanical energy at the crest of the hill. 4-8. b. Olive Udadi is at the park with her father. Trajectory - Horizontally Launched Projectiles Questions, Vectors - Motion and Forces in Two Dimensions, Circular, Satellite, and Rotational Motion. Determine Connor's speed when he strikes the water. A 78-kg skydiver has a speed of 62 m/s at an altitude of 870 m above the ground. Paige is the tallest player on South's Varsity volleyball team. A new conveyor system at the local packaging plan will utilize a motor-powered mechanical arm to exert an average force of 890 N to push large crates a distance of 12 meters in 22 seconds. Determine the work done by Jerome in climbing the stair case. She is in spiking position when Julia gives her the perfect set. NCERT Exemplar Problems Class 9 Science – Work and Energy Multiple Choice Questions (MCQs) Question 1: When a body falls freely towards the earth, then its total energy (a) increases (b) decreases (c) remains constant (d) first increases and then decreases Answer: (c) Since, total energy of the system is always conserved, so when a […] Deadlifting involves raising a loaded barbell from the floor to a position above the head with outstretched arms. b. Sheila (m=56.8 kg) is in her saucer sled moving at 12.6 m/s at the bottom of the sledding hill near Bluebird Lake. Problem C Ch. Spring potential energy example (mistake in math). Paige spikes the ball, doing 9.89 J of work on it. Determine the initial kinetic energy of the Camaro. A 6.8-kg toboggan is kicked on a frozen pond, such that it acquires a speed of 1.9 m/s. We use cookies to provide you with a great experience and to help our website run effectively. Determine the power delivered by the motor to lift the 10 passengers at this speed. Solution : The work-kinetic energy principle: W net = Δ EK. Our mission is to provide a free, world-class education to anyone, anywhere. e. Determine Suzie's speed as she arrives at the end of the run and prior to braking to a stop. A 5000-kg car accelerated from rest to 20 m/s. If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked. d. If no energy is lost or gained between the top of the hill and her initial arrival at the end of the run, then what will be Suzie's total mechanical energy at the end of the run? What is Jerome's kinetic energy before the acceleration period? d. Determine Jerome's kinetic energy at the top of the vertical section. A: Joule B: erg C: g-cm D: Watt. Midway through the run, Bogataj recognized the danger and attempted to make adjustments in order to terminate his jump. This relationship is called the work‐energy theorem: W net = K. E. f − K. E. o, where K. E. f is the final kinetic energy and K. E. o is the original kinetic energy. c. … one-half the mass and was moving with twice the speed? b. Matthew starts from rest on top of 8.45 m high sledding hill. What kinetic energy would the bicycle have if it had …. a. d. Determine Ima's speed at the bottom of the loop. e. … three times the mass and was moving with one-half the speed? b. The 26-kg Olive is on a swing following the path as shown. If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked. Determine Nicholas' potential energy at the top of the slide. Determine the distance which Matthew will slide along the level surface before coming to a complete stop. The combined mass of the passengers and cabin is 1250 kg. Determine the total work done on the squirrel while moving upward (32 times). a. She is moving at 16 m/s across the crest of a ski hill located 34 m above ground level at the end of the run. Determine the net work done on the car. They apply a cumulative force of 1080 N to push the car 218 m to the nearest fuel station. Determine the work done by Sheila on the suitcase. c. Determine the amount of work done on the Camaro during the deceleration. Determine the amount of kinetic energy possessed by Ceres. b. Connor's body plunges to a depth of 2.15 m below the water surface before stopping. A 5000-kg car accelerated from rest to 20 m/s. Misfortune occurs and Renatta and her friends find themselves getting a workout. Nolan Ryan reportedly had the fastest pitch in baseball, clocked at 100.9 mi/hr (45.0 m/s) If such a pitch had been directed vertically upwards at this same speed, then to what height would it have traveled? Determine the power generated by Jerome. Gwen is baby-sitting for the Parker family. During the Powerhouse lab, Jerome runs up the stairs, elevating his 102 kg body a vertical distance of 2.29 meters in a time of 1.32 seconds at a constant speed. Initial speed (v o) = 0 m/s (car rest) Final speed (v t) = 20 m/s. Q.1 What is the SI unit of Work? c. Assuming negligible losses of energy due to friction and air resistance, determine Ima's total mechanical energy at the bottom of the loop (h=0 m). Work and kinetic energy – problems and solutions. e. Determine the speed of the ball upon hitting the floor on the opponent's side of the net. Determine the work done by Lamar in deadlifting 300 kg to a height of 0.90 m above the ground. Determine the distance which the toboggan slides before coming to rest. Determine the average force of water resistance experienced by his body. b. At the top of the slide, Nicholas (m=72.6 kg) is 28.5 m above the ground. c. Once the launch is over, Jerome begins screaming up the 420-foot, completely vertical section of the track. a. Determine Ima's kinetic energy at the top of the loop. a. By the work–Kinetic Energy Theorem, this is equal to the change in kinetic energy of the box: ΔK = K f − K i = W net = 62 J (d) Here, the initial kinetic energy Ki was zero because the box was initially at rest. Justin Thyme is traveling down Lake Avenue at 32.8 m/s in his 1510-kg 1992 Camaro. Applied force vs. position graph of an object is given below. a. Chloe leads South’s varsity softball team in hitting. He is moving with a speed of 23.4 m/s at a height of 44.6 meters above the ground. Sheila has just arrived at the airport and is dragging her suitcase to the luggage check-in desk. c. Determine the total mechanical energy possessed by the skydiver. After descending the 49 m, Vinko tumbled off the track and descended another 15 m down the ski hill before finally stopping. Suppose that the 0.145-kg baseball left Kingman's bat at 92.7 m/s and that it lost 10% of its original energy on its flight through the air. So we have K f = 62 J. Determine the potential energy possessed by the skydiver. Before practicing these mcqs read General knowledge on work power and energy. Determine Suzie's kinetic energy. d. Determine Nicholas' potential energy as he arrives at the bottom of the slide. Renatta Gass is out with her friends. They apply a cumulative force of 1080 N to push the car 218 m to the nearest fuel station. A braking system abruptly brings the 328-kg car (rider mass included) to a speed of 2.9 m/s over a distance of 5.55 meters.