opposing force | Kelly St. Scientists

Since we have explored gravity and how it effects dropped objects (the same regardless of mass) perhaps we should think about what is needed to escape gravity.

In order to do this we need to consider forces.

So we exerted forces on one another with the hula hoops, staying safe of course!

The biggest force was the one that determined the direction.

We really put our backs into exerting our forces!

Lara even used the radiator guard to help her exert more force!

But Gracie gave as good as she got and used a big force too!

But something unexpected happened! As Lara recorded on the logbook.

Lara recorded that the large force placed on the hula hoop broke it!

“We were learning about force and I had quite a lot of force (it was about 20 million) and the hula hoop burst right open!

Lara told her friends about what happened using the word "force"! — Lara told her friends about what happened using the word “force”!

Isla applied most force so she pulled Ryan toward her.

Then we thought about what kind of forces could be made to oppose gravity. Would it need to be a little force or a big force? What difference would the size of the force make? We explored this with our very own rockets!

We were in agreement with our predictions:

Elise: “We’ll need a big force”

Of course we needed to stay safe as always!

“We have to watch – it will fall!”: Caoimhe

“We need to stay on gravity.” Ross M.

“We could go somewhere else.”: Harmony

“We could wear an umbrella on our head”: Isla M.

We went with Ryan D and Gracie’s ideas though.

There was a conversation about the best way to exert the force to make the stomper rocket blast off:

Lara: “You push it like this.”[ Demonstrating with her hands].

Ross M: “No you do it with a foot.”

Caoimhe: “You need to put 2 feet on it – look” [shows the others the picture on the box].

There was some debate over the length of time the rocket would take to fly…

Harmony: “Oh ages – 100 days”

Ryan D.: “25 years”

Elyse: “22”

Ross M.: “100 minutes”

Isla M.: 1 minute

Caoimhe: “50 minutes”

It was a little faster. (In fact it was so fast that the camera couldn’t catch more than a blur!)

We used some of our numeracy skills to help us prepare for blast off. (Counting down helps children understand the sequence of numbers and is the first steps towards subtraction!)

Charlie realised that if you jumped on to the pump you could apply more force. Natalie took a run and jump to get even greater force. Then Euan worked out that he could jump from the step to use gravity to add force!

So the greater the force, the further the rocket would fly.

“Wow – that was a really big force!”: Eve

“If you went slowly it would go a wee bit low.”: Patrick

“Our force made it go up”: Ross M.

We put our hands over the end of the tube tosee what the force felt like.

“So the air pushes it up and up” : Patrick

Sophie applied such force that the rocket jammed and got stuck in the light! We had to get Roseann to bash it out with a big long pole!

So were our predictions right? YES! yes

(With one exception…. “It was faster.”: Harmony)

The rocket bashed off the ceiling most times so we don’t know how high it could go if nothing stopped it. To test that we’ll have to go outside!

(I hope it’s dry on Friday!)

Want to extend the learning at home? Here are some very simple ideas to reinforce you child’s understanding of gravity and forces.

Happy experimenting!

You may have heard and seen onTwitter that the children in the main building have been learning about space recently. Some of this has been by watching clips of Commander Chris Hadfield in the International Space Station

During these clips we have looked at the effect of being away from most of Earth’s gravity, and how this effects daily routines such as washing etc. So we know that little gravity means things float but what does gravity mean on Earth, where it is stronger, and why is it stronger on Earth?

We set out to explore gravity. We started by experimenting to see if all objects are effected the same way – does everything fall? Do some things fall faster/ slower?

We chose our objects and made predictions:

Caoimhe chose to compare the ball and the tiny pom pom. Her prediction was that the ball would hit the ground first.

Caiomhe predicted the ball would land first because "It is bumpy" — Caiomhe predicted the ball would land first because “It is bumpy”

Patrick discovered that it had to be a fair test and that the objects needed to start from the same height and at the same time. His experiment had to be redone twice over to ensure a fair test!

Caoimhe recorded that the height would need to stay the same.

He predicted the swing would land first as "It's heavier". — He predicted the swing would land first as “It’s heavier”.

We tested our hypothesis.

Frazer chose two different sized pine cones. He predicted they would "go together". — Frazer chose two different sized pine cones. He predicted they would “go together”.

"The 2 balls hit the ground first!" — “The 2 balls hit the ground first!”

"They fell together" — “They fell together”

But why don’t you have a look at the predictions and experiments themselves! Look at Holly’s prediction and Ryan’s prediction.

Have a look at Lauren’s experiment, Holly’s experiment, Gaby’s experiment , Amy D’s experiment and the experiments of Finn , Brandon , and An, who goes at 2!

So what happened?

Maybe we should ask for Ryan’s conclusions, Lyall’s gravity explanation or Isla’s conclusion.

“they all fall at the same time ’cause of gravity!” Eve

We reviewed our predictions:

"I'll just do a cross because I was wrong" — “I’ll just do a cross because I was wrong”

Then we looked at hankies – two hankies the same should land at the same time – just as everything else right? Wrong! If one was scrunched up and the other flat, the air resistance made a difference, slowing the flat one.

So everything fell at the same speed unless the air drag slowed it down. The air drag acts as an opposing force.

Hmmmm…………. what else could make an opposing force to gravity?

Want to find out more about gravity? Have a look here or here.

Why not try your own experiments and let us know how you get on!

Science blog from the children and staff of Kelly St. Children's Centre.