Module 5—Circular Motion

Lesson 4 Lab: Acceleration, Weight, and Velocity of Satellites

 

You will continue to use the Weight and Orbits simulation in this lab.

 

Problem 1

 

Do the weight and the acceleration of a satellite change during the satellite's motion? If so, how do they change?

 

Module 5: Lesson 4 Assignment

 

Remember to submit the answers to LAB 1 and LAB 2 to your teacher as part of your Module 5: Lesson 4 Assignment.

 

Procedure 1 

 

LAB 1. Complete the following steps:

  1. Does either the weight vector or the weight value change?

  2. Describe what happens to the direction of the weight vector as the satellite orbits Earth.

  3. Describe what happens to the magnitude of the weight vector as the satellite orbits Earth. If it changes, how can this be explained using Newton’s equations for weight?

Notice that as the satellite orbits, the weight and acceleration vectors vary in the same way. The satellite is not always the same distance from Earth’s centre. This causes the acceleration and, by extension, the weight of the satellite to change.

 

LAB 2. Is the satellite ever "weightless" in any orbit? Experiment with different orbits in different scale settings, and move the satellite as far away as possible. Explain your observations in terms of the equations that describe weight.

 

Problem 2

 

How can you calculate the velocity of a satellite (m1) moving in a perfectly circular orbit?

 

Module 5: Lesson 4 Assignment

 

Remember to submit the answers to LAB 3, LAB 4, and LAB 5 to your teacher as part of your Module 5: Lesson 4 Assignment.

 

Procedure 2

 

LAB 3. Complete the following steps:

Do you see any changes in the force of gravity, the acceleration due to gravity acting on the satellite, or the value of the weight shown in the data box? Explain your observations in terms of Newton's universal law of gravitation. (Specifically, does the force of gravity depend on the velocities of the interacting objects?) 

 

LAB 4. Find out if a projectile can become a satellite, given an appropriate initial velocity and position.

Based on your observations, fill in the blanks with these terms: large, small, parallel, perpendicular.

 

A projectile will become a satellite in a nearly circular orbit when the magnitude of the velocity is ____________ and it is directed ___________ to Earth’s surface.

 

LAB 5. Using a trial-and-error method, try to find the exact horizontal speed that a satellite would need to have at an altitude of 1000 km to make a circular orbit.

 

circular orbit speed = _________________