Background: Look at the wheelbarrow in the Figure below . It is used to carry heavy objects. It consists of two simple machines a lever and a wheel and axle. Effort is applied to the lever by picking up the handles of the wheelbarrow. The lever, in turn, applies upward force to the load. The force is increased by the lever, making the load easier to lift. Effort is applied to the wheel of the wheelbarrow by pushing it over the ground. The rolling wheel turns the axle and increases the force, making it easier to push the load.

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: What lever was used to lift the refrigerator?

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: What force was increased by the lever?

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: Did the lever increase or decrease the applied force?

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: Did the force applied change directions or stay the same?

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: What did the lever make easier?

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: Does the wheel increase or decrease the force?

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: Does the wheel change the direction of the force or keep it the same?

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: Is the refrigerator lifted with or without machines?

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: Is there one or multiple machines involved?

Situation: The refrigerator was the last thing that mark needed to load onto the moving truck. He slid the edge of the dolly under the refrigerator and pushed down on the handle, lifting the refrigerator off the floor. He then pushed on he cart and rolled it out to the truck.

Question: Is the dolly used to increase or decrease force?

Situation: Mark was building new flower beds. He had a lot of edirt and rocks to move. Looking at where the landscaping company had dropped the dirt off at he knew he needed to find a way to move it. Matt loaded the large bags of soil into a wheelbarrow. Pushing down on the handle he pushed the wheelbarrow forward so that it rolled on it's wheel.

Question: Is the wheelbarrow a plane or a lever/

Situation: Mark was building new flower beds. He had a lot of edirt and rocks to move. Looking at where the landscaping company had dropped the dirt off at he knew he needed to find a way to move it. Matt loaded the large bags of soil into a wheelbarrow. Pushing down on the handle he pushed the wheelbarrow forward so that it rolled on it's wheel.

Question: Did the wheelbarrow apply upward or downward force on the load?

Situation: Mark was building new flower beds. He had a lot of edirt and rocks to move. Looking at where the landscaping company had dropped the dirt off at he knew he needed to find a way to move it. Matt loaded the large bags of soil into a wheelbarrow. Pushing down on the handle he pushed the wheelbarrow forward so that it rolled on it's wheel.

Question: Did the wheelbarrow increase or decrease the force?

Situation: Mark was building new flower beds. He had a lot of edirt and rocks to move. Looking at where the landscaping company had dropped the dirt off at he knew he needed to find a way to move it. Matt loaded the large bags of soil into a wheelbarrow. Pushing down on the handle he pushed the wheelbarrow forward so that it rolled on it's wheel.

Question: Does the wheel increase or decrease force?

Situation: Mark was building new flower beds. He had a lot of edirt and rocks to move. Looking at where the landscaping company had dropped the dirt off at he knew he needed to find a way to move it. Matt loaded the large bags of soil into a wheelbarrow. Pushing down on the handle he pushed the wheelbarrow forward so that it rolled on it's wheel.

Question: Does the wheel make it harder or easier to push?