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Bubba has a mass of 100 kg on the earth. What is Bubba's mass on the moon where the force of gravity is approximately 1/6-th that of Earth's? Billie weighs 360 N on Earth. What is Billie's mass on the moon where the force of gravity is approximately 1/6-th that of Earth's? The amount of net force required to keep a 5-kg object moving rightward with a constant velocity of 2 m/s is ____. a. 0 N b. 0.4 N c. 2 N d. 2.5 N e. 5 N f. None of the above. Which one(s) of the following force diagrams depict an object moving to the right with a constant speed? List all that apply. During which time interval(s), if any, do you know there are no forces acting upon the object? List all that apply. During which time interval(s), if any, are the forces acting upon the object balanced? List all that apply. A rocket is flying toward a distant galaxy. Suddenly, the pilot realizes they are out of fuel. The rocket will____________ a) b) c) d) arrive at the galaxy at the same speed they are moving. arrive at the galaxy and stop. stop before reaching the galaxy. stop, then start moving in the opposite direction. A 50kg box sits motionless on a ramp, as shown below. Draw the force diagram for the box. What is the magnitude of the normal component of the force of the ramp on the box? 20° A 50kg box slides at 4 m/s down a ramp, as shown below. Draw the force diagram for the box. What is the magnitude of the normal component of the force of the ramp on the box? v 20° For an object resting upon a non-accelerating surface, the normal force is equal to the weight of the object. According to Newton's third law, every force is accompanied by an equal and opposite reaction force. The reason that these forces do not cancel each other is ____. a. the action force acts for a longer time period b. the two forces are not always in the same direction c. one of the two forces is greater than the other d. the two forces act upon different objects; only forces on the same object can balance each other. e. ... nonsense! They do cancel each other. Objects accelerate because of the presence of a third force. As you sit in your chair and study your physics (presuming that you do), the force of gravity acts downward upon your body. The reaction force to the force of the Earth pulling you downward is ___. a. the force of the chair pushing you upward b. the force of the floor pushing your chair upward c. the force of the Earth pushing you upward d. the force of air molecules pushing you upwards e. the force of your body pulling the Earth upwards f. ... nonsense! Gravity is a field force and there is no such reaction force. When a NASA space shuttle is flying into space, what object pushes the shuttle forward? a. The shuttles rockets. b. The air behind the shuttle. c. The earth. d. The gas being released. e. None of the above. While minding your own business one day in the hallway, someone comes up to you and slams you into the wall. Draw accurate, labeled force diagrams for each of you during the time you are held on the wall. List all of the objects that Block A exerts a force on. Block A 15kg Block B 5kg Block C 10kg Draw labeled force diagrams for each of the blocks. Block A 15kg Block B 5kg Block C 10kg Using g=10m/s2, attach values to each of the forces in your diagrams. Block A 15kg Block B 5kg Block C 10kg If the table were placed on a cart and rolled down the hallway, which forces would change? Block A 15kg Block B 5kg Block C 10kg If the table were placed in an elevator moving up at a constant speed, which forces would change? Block A 15kg Block B 5kg Block C 10kg Three pictures of equal weight (20 N) are hung by wires in three different orientations. In which orientation are the wires least likely to break? A car is moving toward the right. Then a force is applied causing the force diagram to look as shown below. Draw the position vs. time graph. Use the approximation that g=~10 m/s2 to fill in the blanks in the following diagram. Fair on block = _______ N FEarth on block = _______ N m = 80 kg a = 2.0 m/s2 down A person pushes the block up the frictionless ramp (which makes an angle of 45 to the horizontal). Draw a force diagram for the block. m = 30 kg a = 2.0 m/s2 up the ramp A person pushes the block up the frictionless ramp (which makes an angle of 45 to the horizontal). Use the approximation that g=~10 m/s2 to find FEarth on block. Fperson on block Nramp on block FEarth on block = _______ N m = 30 kg a = 2.0 m/s2 up the ramp A person pushes the block up the frictionless ramp (which makes an angle of 35 to the horizontal). Use the approximation that g=~10 m/s2 to find Nramp on block. Fperson on block Nramp on block = _______ N FEarth on block = _______ N m = 30 kg a = 2.0 m/s2 up the ramp A person pushes the block up the frictionless ramp (which makes an angle of 35 to the horizontal). Use the approximation that g=~10 m/s2 to find Fperson on block. Fperson on block = _______ N Nramp on block = _______ N FEarth on block = _______ N m = 30 kg a = 2.0 m/s2 up the ramp