10.0 kg bowling ball falls from a 5.0 m shelf. Just before hitting the floor, what will be its kinetic energy? (g = 9.80 m/s2 and assume air resistance is negligible) A 10.0 kg bowling ball falls from a 5.0 m shelf. Just before hitting the floor, what will be its kinetic energy? (g = 9.80 m/s2 and assume air resistance is negligible)

What is the potential energy of an acorn falling out of a tree 20 meters above the ground that has a weight of 23.7 N? O 474 J O 119J O 0.84J O 4645 J

A shooting star is the trail of a meteor - a chunk of debris hurtling through Earth’s atmosphere. As drag slows down the meteor, its energy is converted into thermal energy. A typical meteor may only weigh 2 grams, and enters the Earth’s atmosphere at a speed of 100,000 mph. Assuming that all of its energy is converted into thermal energy over a time of just 3 seconds, what is the power output of the shooting star? How does this compare to the power output of a typical household lightbulb?

A 2-kg brick is thrown downward from a height ?1 = 15 m to ?2 = 10 m. The initial kinetic energy of the brick is ??1 = 25 J. You can use ? = 10 m/s for convenience of calculation.  Assume air resistance is negligible, and nothing heats up or uses fuel during the motion of the brick.1.  If the system of interest is the brick alone, how much work is done by external forces during this motion?

How much work must be done by frictional forces in slowing a 1000.0 kg car from 19.8 m/s to rest? O 6.22 x 105 J 1.96 x 105 J 5.33 x 105 J 4.44 x 105 J 3.55 x 105 J

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Your answer is partially correct. The (non-conservative) force propelling a 1.10 x 10-kg car up a mountain road does 7.50 x 106 J of work on the car. The car starts from rest at sea level and has a speed of 26.0 m/s at an altitude of 2.20 x 102 m above sea level. Obtain the work done on the car by the combined forces of friction and air resistance, both of which are non-conservative forces. Number 4757000 Units eTextbook and Media Hint Save for Later Attempts: 4 of 10 used Submit Answer h 77% 74°F Mostly 画 Home End Insert F5 F6 F7 F8 De F9 F10 F1 F12 % Bac 7 8 R Y U | G H J K L VBN M

10. A 0.58-kg ball is thrown vertically upward with an initial speed of 13.5 m/s. What is the potential energy of the ball when it has travelled three-quarters of the distance to its maximum height? (Use reference point of measurements of the heights) 50 ssr sf60 ss sf60 s 60 091S

4. This Olympic skeleton athlete slides down an icy track head first. The track has many twists and turns with a total height of 102.75 m. If the 99.375 kg man has a speed of 27 m/s at the bottom, what was the total work done on him by friction and air resistance slowing him down? (In other words, what was the energy lost to friction and air resistance?) He starts from rest at the top. 6.3843e4 Previous submissions: -63.84 63.84 63843 J J incorrect

A 0.31-kg particle has a speed of 3.0 m/s at point A and kinetic energy of 8.2 J at point B. (a) What is its kinetic energy at A? (b) What is its speed at point B? m/s (c) What is the total work done on the particle as it moves from A to B?