Gravitational Force
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※ Download: Gravitational force gizmo answer key
The greater the planet's mass, the more gravity pulled on the ball. Students are not expected to know the answers to the Prior Knowledge Questions. The ball lands at the pitcher's feet each time.
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Gravity always pulls the ball toward the center of Earth. This technology could become the basis of a new field of gravity-wave astronomy. Sketch the pitcher and the trajectory of the ball on the diagram.
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Gravitational Force - Observe: Look at the Planet mass and Planet radius of Venus. How is gravity communicated between objects?
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Read Student Exploration Sheet: Growing Plants text version Student Exploration: Gravity Pitch Answer Key Vocabulary: escape velocity, gravity, orbit, orbital velocity, trajectory, velocity Prior Knowledge Questions Do these BEFORE using the Gizmo. Students are not expected to know the answers to the Prior Knowledge Questions. Young Alice age 2 tosses a rock over the edge and giggles as she watches it fall. Brother Darrell age 8 thinks he can do better and hurls another rock over the edge. Papa Billy chuckles, picks up a nice round rock, and flings it off the cliff as hard as he can. In the picture to the right, draw the trajectory, or path, that each rock would take. What would happen if Billy could throw the rock as fast as a rocket? Use the slider to set the Velocity to 0. Velocity is basically the same thing as speed, but has direction as well. In this case the pitcher is simply. What direction does the ball go? Sketch the pitcher and the trajectory of the ball on the diagram. All dropped balls should go toward Earth's surface. Click Reset and drag the pitcher to several new positions. Click Play and watch him drop the ball each time. Sketch the pitcher and the trajectory of each ball on the diagram. What do you notice? The ball lands at the pitcher's feet each time. The ball is pulled by a force called gravity. In what direction does gravity always pull the ball? Gravity always pulls the ball toward the center of Earth. Activity A: How far does it go? Get the Gizmo ready: · Click Reset. · Drag the pitcher back to the top. · Set the Velocity to 1. Question: Why do objects go around, or orbit, other objects? Observe: Click Play and observe the trajectory of the ball. The pitcher is rather tall about 1500 km, or 930 miles, tall! Predict: How would the trajectory of the ball change as the pitcher throws it harder and harder? Explain below, and draw several predicted trajectories on the diagram. Check student work on the diagram. For forward button each throw, sketch and label the trajectory and record the Distance traveled in the table. As the velocity increases, the ball goes farther before it hits the Earth. Draw conclusions: What force causes objects to stay in orbit? Gravity causes objects to stay in orbit. If the orbit is circular, the rate of falling matches the curvature of Earth. If the ball is thrown fast enough, it escapes, never to be seen again. Get the Gizmo ready: Activity B: Comparing planets · Click Reset. · On the Planet menu, choose Venus. Question: How would the gravity of other planets affect a pitched ball? Observe: Look at the Planet mass and Planet radius of Venus. The mass of a planet is how much matter it contains. The radius of a planet is the distance from the center to the surface. Compared to Earth, what are the mass and radius of Venus? Predict: Will the pitcher have to throw the ball faster or not as fast to send a ball into orbit around Venus? Run Gizmo: Orbital velocity is the velocity needed to make a circular orbit. Use the Gizmo to find the orbital velocity of the ball on Venus. Make the orbit as circular as you can. What is the orbital velocity on Venus? Do the same on Earth. What is the orbital velocity on Earth? Based on this, which planet do you think has stronger gravity, Venus or Earth? Earth's gravity is stronger. It requires a higher velocity to orbit Earth. Estimate what the orbital velocity will be on Mars: Answers will vary. Why did you choose that value? Run Gizmo: Adjust the Velocity until you create a circular orbit on Mars. What is the orbital velocity on Mars? How does gravity on Mars compare to Earth and Venus? Much weaker on Mars. Extend your thinking: The escape velocity is the smallest velocity needed for the baseball to escape from the planet's gravity and fly off into space, never to return. Which planet do you think has the lowest escape velocity? Use the Gizmo to test your prediction. Get the Gizmo ready: Activity C: Design a planet · Click Reset. · On the Planet menu, select Custom. · Set the Velocity to 7. Question: How does a planet's mass and radius affect a pitched ball? Observe: Using the sliders, try a variety of values for Planet mass and Planet radius for your custom planet. Observe the trajectory of the ball each time. Form hypotheses: Fill in the blanks below: As its mass increases, the strength of a planet's gravity Increases Hypotheses will vary. As its radius increases, the strength of a planet's gravity Decreases Hypotheses will vary. Run Gizmo: Set Planet mass to 0. Press Play and record results. Repeat for masses of 1. The ball went in a straight line to outer space. The ball orbited the planet and hit the pitcher. The ball hit the ground in front of the pitcher. Analyze: How does increasing the mass affect the gravity of the planet? How do you know? Increasing mass increases the strength of gravity. The greater the planet's mass, the more gravity pulled on the ball. Experiment: Do the same kind of experiment, but now keep the Planet mass at 1. Record results in a notebook or on a separate sheet of paper. What do you notice? As the radius increases, the ball travels farther. How does changing the radius affect the strength of a planet's gravity? As radius increases, gravity gets weaker. Apply: Using what you have learned, create a planet with the strongest possible gravity. What are the mass and radius of this planet?
Based on this, which planet do you think has stronger gravity, Venus or Earth. The pitcher is rather tall about 1500 km, or 930 miles, tall. Young Alice age 2 tosses a rock over the edge and giggles as she watches it fall. Run Gizmo: Set Planet mass to 0. Gravity always pulls the ball toward the center of Earth. Observe: Click Play and observe the trajectory of the ball. Each lesson comes with a complete set of lesson materials. Why did you choose that value. Extend your thinking: The escape velocity is the smallest velocity needed for the baseball to escape from the planet's gravity and fly off into space, never to return. Gizmos is an online learning tool created and managed by ExploreLearning. How does gravity on Mars compare to Earth and Venus?.