Science: Inclined Planes and Wedges

Today we discussed Inclined Planes and Wedges as our 4th and 5th Simple Machines. An Inclined plane is pretty much a ramp (stairs count as well) and a wedge is like a doorstop. Other examples of wedges include knives, teeth and other cutting tools).

There was no homework for this lesson today.

Science: Pulleys

Today we talked about pulleys. There are three types of pulleys: Fixed, moveable and combined. We did an experiment as a class to look at the advantages of each type of pulley. Students were to fill out a chart that explains the advantages and disadvantages of each pulley. They are also to come up with 3 examples of pulleys. This work is homework.

Science: Levers

Today we talked more about levers. We discussed how levers give us an advantage and we looked at three different types of levers. Students wrote in their book about 1st, 2nd and 3rd class levers and were asked to find examples of each for homework.

Science: Levers

Today I introduced the first simple machine we will be talking about, Levers. I gave students a diagram of levers to copy and we started an experiment to look at the different amount of force needed when we move where the fulcrum is.

There was no homework for this section.

Science: Work and Machines

Today we talked about the scientific definition of work: using a force to move an object. We also talked about the definition of a machine: something that makes work easier.

I had the students try three tasks: push against a wall, lift a textbook, and pull their chair across the floor. The students were to draw a picture, put one arrow in the direction they applied the force, put another arrow in the direction the object moved, and write whether or not worked occured. This is homework if not finished.

Science: Review of Forces

Today we did a review of the work we have done with forces. I mentioned to the class that there will be a quiz next week (likely on Wednesday).

I gave the students a list of words and concepts they need to know for this quiz. If students do not know they are free to ask me, but not on the day of the quiz:

• force
• weight
• mass
• friction
• ramp
• load
• balanced forces
• unbalanced forces
• equilibrium
• spring scale

Science: Balanced Forces

Today in Science we started talking about balanced forces and equilibrium. This led into a discussion about gravity and how some objects fall faster than others (and why most objects fall at the same rate). There was no homework for this lesson.

Science: What Affects How Much Force We Need

Today in Science we talked about the different factors that affect how much force you need to move an object. We briefly reviewed yesterdays lesson on friction and brainstormed several other situations in which you might need more or less force.

We did an exploration as a class with what happens when you add things to a bag (the force you need goes up) and what happens when you increase the steepness of a slope (the force you need goes up). There is no homework for this section.

Science: Friction

Today we talked about Friction. We discussed how friction is related to surface texture (rough surfaces create more friction and smooth surfaces create less friction). We also talked about advantages and disadvantages of friction.

The homework for tonight is to finish the sheet called "Section 1.3: Friction." Students only need to complete the front side of that page. We will be working with the back side of the page tomorrow so they should remember to bring back their sheet.

Science: Measuring Forces

Today in Science we talked about the difference between Mass and Weight. Mass refers to how much of something there is and Weight refers to how much the force of gravity pulls down on something.

We looked at spring scales and how to use them and the class made their own out an elastic, a pencil and a ruler. They used their scales to measure the weight of some classroom items.

There is no homework for today's science lesson.

Science: What Makes Things Move?

Today in Science we talked about forces and how objects move. We discussed many ways objects can move and talked about forces as pushes or pulls. We looked at how a ball bounces and how we can change the height the ball bounces. We also did an experiment involving how high a ball bounces on different surfaces.

These are our results:

Surface	Trial #1	Trial #2	Trial #3
Baseball Bag	45cm	34cm	30cm
Floor	65cm	70cm	75cm
Cardboard	69cm	70cm	74cm

The homework is to answer three questions at the bottom of the page titled: How Does Floor Surface Hardness Affect How High a Ball Bounces?:

1. Which surface resulted in the highest bounce?
2. How does the hardness of the floor surface affect how high a ball bounces?
3. Did your results fully support, partly support, or not support your prediction.

We also had question from the textbook:

1. Think about riding a bike or going skateboarding. Choose one of these activities and describe, in words or pictures, how force is used to:
• start and stop moving
• change speed
• change direction