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1. Two objects 15m apart both have the same charge. If the force on one of them is 0.0349N what is the charge (in μC ) on the other object?

2. The electric field intensity 25.7 m away from a charged sphere is 6.54 N/C. What charge (in μC) has been added to the sphere?

3. How much work (in J) is required to move 1.6 mC of charge from a distance of 3.44 m to a distance 1.3 m from a charge of 3.21 μC?

4. Three charges are fixed as shown, with Q1 = - 4.56 μC, Q2 = 2.99 μC, and Q3 = 1.59 μC. Find the force on a proton located at point P. Express the direction of the force in terms of degrees below the x-axis.

5. An electron (q = 1.6 x 10-19C; m =9.11 x 10-31 kg) accelerates from rest through a potential difference of 296.8 V. What is the electron's final speed (in m/s)?

6. Box A with a mass of 3.35 kg and box B with a mass of 1.28 kg are attached by a light string slung over a pulley. Box A slides along a smooth horizontal surface as box B falls. When released, box B falls 84 cm to the floor. Ignoring frictional effects, what is the maximum kinetic energy of box A before box B hits the floor?

7. A hiker travels 1.92 m/s up a slope inclined at 21.3 º above the horizontal. The slope is 34.8 m long. How much power (in W) does the hiker expend to get up the slope if he and his equipment have a mass of 100.0 kg?

8. A 49.9 kg sled slides across the ice and a 13.2 kg package is dropped vertically down onto the sled. What is the ratio, KEf/KEi, of the kinetic energy of the sled and package to the kinetic energy of the sled before the package was dropped?

9. A forklift is used to raise a 196 kg load from the floor to a height of 3.02 m. If the forklift expends 1752 W of power, how many seconds does it take to lift the load?

10. A block is released from rest at a vertical height of 40.5 cm on a plane inclined at an angle of 21.3 º from the horizontal and slides down the plane, reaching a speed of 1.36 m/s at the bottom. What is the coefficient of friction between the block and the plane?

11. A 58-kg buoy is anchored by a light rope to a cement pad. The buoy displaces 24.5 kg of water. What is the tension (in N) on the rope?

12. If water flowed through a pipe with a diameter of 14.6 mm at 2.61 m/s, how fast (in m/s) would it flow through a pipe with a diameter of 23 mm?

13. A large tank is filled with water to a depth of 11.1 m. A spout is opened a height of 6.98 m above the bottom of the tank. What is the speed (in m/s) of the water through the spout?

14. What is the total pressure (in Pa) at a depth of 674 m of water when the air pressure is one atmosphere?

15. What pressure in atmospheres (above atmospheric) is required to send water to a height of 77.7 m?

16. The moon has an orbital period of 27.3 days and a mean distance of 380000 km from the center of the Earth. Find the distance (km) an artificial satellite is from the center of Earth if its period is 86.8 minutes.

17. A planet has two moons. the first is 4 times as far from the center of the planet as the second and has a mass that is 3 times the mass of the second. What is the ratio of the gravitational force on the first planet to the gravitational force on the second?

18. Two spherical balls are placed so their centers are 3.8 m apart. The force between them is 27.4 nN. If the mass of the smaller ball is 69.9 kg, what is the mass (in kg) of the other ball?

19. How far (in km) from the center of the Earth would a person with a weight of 457 N on Earth have to be to have a weight of 55.4 N?

20. A 16.7 kg child is sitting on a merry-go-round with a radius of 6.25 m. The time it takes the merry-go-round to make one revolution is 4.34 s. Find the centripetal acceleration of the child.


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