GRADE SIX SCIENCE
Hello Boys and Girls, Did you have a good week? Did you have an exciting first week at school? Please be focused on your work. Work hard and do well. This is a special year for you, the year of your National Assessment to which you are looking forward. Revision is key to your success. Be ready for school tomorrow. Ensure that everything is in order. Have a good term.
Last week we looked at pulleys. Do you remember what we found out? Check yourself. i. What is a pulley? ii. Describe a pulley. iii. Name at least two places where pulleys can be found. iv. Draw a fixed pulley. Draw a moveable pulley. This week we will investigate another simple machine, the wheel and axle.
The wheel is a great invention. We can hardly do without it. The wheel by itself, however, is not a simple machine. A wheel by itself is simply a roller. Maybe the idea of a wheel came about from rolling logs along the ground many years ago. The wheel and axle has been around for some 7,000 years.
The wheel is part of a simple machine called the wheel and axle. The axle is a smaller wheel fitted tightly in the larger wheel. It works along with the larger wheel.
Every time you turn a doorknob you are using a wheel and axle. If there were no knob on the rod that goes through a door, it would be difficult to open the door. The knob makes it easier to work the latch.
The knob is a wheel. The rod is an axle. The wheel and axle work together to open the door. A wheel and axle is used in many machines. The wheel and axle helps is to do work in many ways. This simple machine makes it easy to turn things and to move things. The wheel is attached to the axle so that these two parts rotate together. Here a force is transferred from one to the other.
Do you know what a windlass is? If you don’t, please find out before moving on.
A windlass is a kind of wheel and axle. It has a horizontal axle for hauling or hoisting. A windlass The principle of the windlass Making a wheel and axle Attach the small wheel to one end of the rod and the large wheel to the other. Attach a weight or load to the axle.
Now turn one wheel completely around. Observe the distance through which your load is moved. Turn the other wheel completely around and also observe the distance through which it is moved. You will find that whether the small wheel or the big wheel is used the distance is the same. Experiment with your wheel and axle as much as you would like to.
Experimenting with your wheel and axle Large wheels are used on a wheel and axle to make work easy. Scientists have found that the larger the wheel, the easier the work. Large trucks, for example, have big steering wheels. The large steering wheel makes it easy for the driver to guide the truck. It would be quite difficult to get a truck around a corner with a small steering wheel.
Try to identify places where the wheel and axle can be found and identify them. Did you check you egg whisk and all those knobs that you turn? Do you see how simple machines help to make work easier and improve the quality of our lives? Here are a few questions for you. 1 Name five classes of simple machines. 2 Place X near to each correct example of a simple machine. a. pulley._______________ b. wheel.________________ c. scissors________________ d. wheel and axle___________ e. steps___________________ f. seesaw__________________ g. drink opener_______________ _____________,_________________,_____________ are all exam3
ples of lever. 4 State three functions of simple machines. 5 Which simple machine does one usually find on a flag pole? 6 Name at least six wheel and axles. 7 Study the pictures of the wheel and axels below. Discuss them with
Next week,. we will look at Inclined Planes and Wedges. Until then, goodbye, Boys and Girls. Revise! Revise! Revise!
Early man rolling a log