Open Question: please help me with this basic physical science?

1. What nice of friction occurs as a fish swims through water? (1 point) fluid rolling sliding static 2. As you push a cereal box across a tabletop, the sliding friction acting on the cereal box _____. (1 point) acts in the direction of motion equals the weight of the box is usually greater than static friction acts in the direction opposite of motion 3. The forces acting on a falling leaf are _____. (1 point) air resistance and fluid friction gravity and air resistance gravity and static friction weight and rolling friction 4. An orange might roll off your cafeteria tray when you cease suddenly because of _____. (1 point) the balanced forces acting on the orange the centripetal force acting on the orange the friction forces acting on the orange the orange’s inertia 5. In which of the following are action and reaction forces involved? (1 point) when a tennis racket strikes a tennis ball when stepping from a curb when rowing a boat every of the over 6. The product of an object’s mass and velocity is its _____. (1 point) centripetal force momentum net force weight 7. What is conserved when two objects collide in a closed system? (1 point) acceleration momentum speed velocity 8. When opposite poles of two magnets are brought together, the poles _____. (1 point) attract each other repel each other cancel each other cause a net force of zero 9. Which of the following universal forces is the weakest? (1 point) electric gravitational magnetic strong nuclear 10. The force that keeps an object moving in a circle is called _____. (1 point) centripetal force fluid friction inertia momentum 11. A brick weighs 26 N. Measured underwater, it weighs 11 N. What is the size of the buoyant force exerted by the water on the brick? (1 point) 37 N 26 N 11 N 15 N 12. A ball is floating partially submerged in a liquid. The buoyant force acting on the ball equals the _____. (1 point) volume of the ball below the surface volume of the ball over the surface mass of the ball weight of the ball 13. Which of the following substances will sink in glycerin? (The density of glycerin is 1.26 g/cm3.) (1 point) water (1.00 g/cm3) ethyl alcohol (0.81 g/cm3) benzene (0.90 g/cm3) aluminum (2.70 g/cm3) 14. A cork is floating in salty water. As more salt is added to the water to increase its density, the cork will _____. (1 point) float at a higher level in the water float at a lower level in the water sink float at the same level in the water

8 Mar 2010, 3:47 pm | click here to view more