Gravity



 =The Objective:=

You will: Label all forces and vectors that are affecting this demonstration Vary the mass of the cart by placing metal bars or masses on the cart. Vary the force by changing the hanging mass. Measure the acceleration indirectly by measuring time.

=Materials Needed:= Cart or toy car that can be attached with string. Pulley to allow the string to be attached to the cart and the hanging mass. Set of masses: Total of 200g. Timers Download the handouts for this activity | =Setup:= A cart or toy car is pulled by a string connected to a hanging mass. As the force (the hanging mass) and the mass of the cart are varied, the relationships can be observed. =Background Information:= Students should already understand that an object has weight which is a force. Students should know that an object speeding up from rest is undergoing acceleration. The cart is m (the mass) in F = ma. The weight of the hanging mass is F (the force) in F = ma. Fw = mg. The force of weight is mass times the acceleration of gravity (10). The acceleration (“a”) is not easily measured. A shorter length of time for the cart to move a set distance indicates a greater acceleration. The magnitude of “a” is not necessary.   =Data to Collect:=
 * Changing Force**

Observations: