Identify the following scientists. 1. Ancient Greek who incorrectly stated that heavy objects fall faster than lighter objects and a constant force was required to keep objects in motion. 2. Scientist who used experimentation to show that heavy and light objects will fall at the same rate (in the absence of air resistance) and that objects will continue to move forever if there are no forces acting on them. 3. Scientist who defined the terms mass and force and developed laws of motion. Unscramble the following terms and Match them with the correct definition. Write the word and the letter that corresponds to the correct definition. 1. IRATENI A. A push or a pull. 2. THEWIG B. Measure of the inertia of an object. 3. REEFCONT C. Tendency of an object to resist changes in motion. 4. COFER D. The measure of the force of gravity acting on an object. 5. SAMS E. The sum of all the forces acting on an object. Identify the SI unit for each of the following. 1. Acceleration 2. Mass 3. Force 4. Weight 5. Speed Neil Armstrong was the first person to step foot on the Moon. NASA determined his mass, including space suit and equipment, while he was still on Earth and it was 120 kg. The acceleration due to gravity on the moon is about one sixth of that of Earth, or 1.6 m/s2. 1. What is the weight of Neil on Earth? 2. What is the mass of Neil on the Moon? 3. What is Neil’s weight on the Moon? 1. Draw a picture of a car with balanced forces acting it. 2. Draw a picture of a car with unbalanced forces acting it. 3. Indicate under each drawing whether each car is accelerating or traveling at a constant speed. Complete each statement or answer the question. The image below shows the forces acting on a falling skydiver. 1. The upward arrow represents the force of ______________. 2. The downward arrow represent the force of _____________. 3. What is the net force on the skydiver? 4. Are the forces balanced or unbalanced? 800 N 5. Is the skydiver speeding up, slowing down, or traveling at a constant velocity? 6. Since the upward force is equal to the downward force the skydiver is at ____________ velocity. 800 N Complete the following by filling in the blanks with the appropriate word or words. ____(1)______ cause objects to accelerate. Forces can result in an object ______(2)______, ______(3)______, or changing _____(4)_________. 1. What is the net force acting on Santa’s bicycle? 2. Are the forces acting on Santa and his bicycle balanced or unbalanced? 3. Is Santa speeding up, slowing down or traveling at a constant velocity? 4. If Santa and the bicycle have a combined mass of 100 kg, what is Santa’s acceleration? 100 N 50 N The image below shows a basketball at various points as it travels through the air. Ignore effects of air resistance. 1. The motion of the ball through the air is an example of ______________ motion. 2. The curved path of the ball is caused by a combination of the downward force of __________ and the initial horizontal velocity. 3. Because there are no horizontal forces acting on the ball the horizontal velocity increase/decreases/stays the same. 4. Draw a force diagram for the basketball while it is traveling through the air. B A C A baseball is thrown straight up into the air. At the very top of its trajectory,… 1. What is the speed of the baseball? 2. What is the acceleration of the baseball? 3. Draw a force diagram for the ball at the top of its trajectory. Answer the following questions. 1. Friction always acts in the opposite/same direction as the object’s motion. 2. It takes more force to get an object moving than the keep it moving because ___________ friction is always greater than __________ friction. 3. Air resistance is an example of ___________ friction. 4. What type of friction would act on a skateboard? In the absence of air resistance which will hit the ground first? 1. A bowling ball or a golf ball that are dropped from the same height? A. The rock B. The penny C. They hit at the same time. 2. A baseball that is hit horizontally at 70 m/s or a baseball that is dropped from the same height. A. The baseball that was hit. B. The baseball that was dropped. C. They both hit at the same time. 1. Two skateboarders face each other on identical skateboards. Skateboarder A pushes on skateboarder B with a force of 30 N to the right. According to Newton’s third law, with what force does skateboarder B push on skateboarder A? 2. What is the acceleration of skateboarder B if her mass is 60 kg? 3. Skateboarder A has a mass of 75 kg. His acceleration will be greater than/less than/equal to that of Skateboarder B. 30 N 1. The gravitational force between two objects depends on what two factors? 2. If the mass of the objects increase, the force of gravity between them _____________. 3. If the distance between two objects increases, the gravitational force between them ________________. 1. A student sets his backpack next to him on the seat of the bus. The driver stops suddenly. A. What happens to the backpack? B. Why? C. Which one of Newton’s laws does this demonstrate? 1. Hot gases are pushed out the bottom of a rocket when it is launched. If the action force is the rocket pushing on the hot gases, what is the reaction force? 2. If the rocket pushes the gases downward out the bottom of the engines, in what direction do the gases push the rocket? 3. This is an example of Newton’s ____ Law. A baseball has a mass of 0.15 kg. The ball is hit by a baseball bat and it accelerates at a rate of 130 m/s2. What force does the bat exert on the ball? REGULAR Draw a force diagram for a 8 N wagon that is being pulled with a force of 10 N. The frictional force on the wagon is 7 N. Label each force arrow with both a name (weight, normal, friction, etc.) and its magnitude. ADVANCED If Marvin the Martian has a mass of 30 kg, what is the gravitational force on Marvin when he is standing on the surface of Mars. Mass of Mars=6.4 x 1023 kg Radius of Mars=3.4 x 106 m G=6.67 x 10-11 Nm2/kg2 FG G m1m2 d2 Explain using Newton’s 2nd Law why it is more difficult to accelerate a loaded wheelbarrow than an empty wheelbarrow.