Ch. 9&10 worksheet Galloway-PHYS 1310
Journal – page 9
Gravity
1. Calculate your gravitational attraction (force in N) to the instructor at the front of the
class. Is this a big number or a small one?
2. Consider two blobs on opposite sides of the earth (A & B). Due to the moon's
gravitational attraction, do they tend to spread away from each other or approach
each other? Does this spreading produce ocean tides?
Moon
Earth
Satellite & Projectile Motion
I. In drawing A, the ball is dropped. Use the scale 1 cm:5 m and draw the positions of
the dropped ball at 1 s intervals. (come to class for drawings!)
In drawing B, the ball is thrown horizontally. The positions of the ball with NO
gravity are shown at the top. Draw the positions of the ball with gravity. Neglect
air drag and assume g = 10 m/s^2. Connect the positions with a smooth curve to
show the path of the ball.
II. In the drawing a satellite with an elliptical orbit is depicted. At the positions
marked, draw an arrow to show the force and another one for the velocity. Try to draw
equal magnitudes with equal lengths and larger magnitudes with longer arrows, but
don't worry about making the scale correct.
Is the force the same magnitude everywhere?
Is the velocity the same everywhere?
Is the angle between force and velocity the same everywhere?
Is work done on the satellite when there is a component of F along and in the same
direction of V and if so, does this increase or decrease the KE of the satellite?
A
B
