New One

Question 1

Why does a helicopter spin?

Answer 1

Because when they spin it creates lift delaying the descent or allowing it to go up.

Question 2

Why don’t you fall through the floor?

Answer 2

Because it is a balanced force both objects are acting upon each other the same.

Question 3

What are forces?

Answer 3

Forces can be contact or non contact forces. They can be a push, pull or twist.

Question 4

What are contact forces?

Answer 4

Contact forces are forces that require contact to work, such as friction, thrust and air resistance.

Question 5

What are non-contact forces?

Answer 5

Non-contact forces don’t require contact to work some examples are, gravity, electrostatic and magnetic.

Question 6

How do we represent forces?

Answer 6

We represent forces with arrows called force arrows, the size and the direction determine how strong and which direction the force is.

Question 7

What holds water on a coin?

Answer 7

Surface area the larger the coin the water it can hold and the surface tension can also determine how much water it can hold. Soapy water has less surface tension making it slip off easier.

Question 8

What is mass and by what unit is it measured?

Answer 8

Mass is how much matter is in an object it is measured in kg.

Question 9

What is weight and what is it measured in?

Answer 9

Weight is the size of the gravitational force acting on an object, it is measured in newtons.

Question 10

What is air resistance?

Answer 10

Air resistance is the frictional force air exerts against a moving object.

Question 11

What is friction?

Answer 11

Friction is a force applied to the surface of an object when it moves against the surface of another object.

Question 12

When is friction a good thing?

Answer 12

Your shoes need to grip the floor so that you can exert a backwards friction force on the floor. In turn, the floor exerts a forward friction force on your shoe in the opposite direction, causing you to move forward.

Question 13

When is friction a bad thing?

Answer 13

When you want to move something heavy, because heavier objects experience more friction making it hard to move.

Question 14

How can friction be reduced?

Answer 14

Answers will vary. Examples include: using lubricants - for example, in car engines where oil is used to lubricate between the two surfaces - for example, sharpening the blades of ice-skates; using ball bearings - this allows relative motion between two surfaces, such as the axle and wheel hub of a skateboard.

Question 15

What is density and how do you calculate density?

Answer 15

Density is the measurement of how tightly packed matter is in an object. You measure it using the formula Density = mass/volume.

Question 16

What type of machine is a seesaw?

Answer 16

It is a lever, more specifically a first class lever.

Question 17

What are the three different types of levers? What are some examples of each of these?

Answer 17

There is first class, second class and third class levers, an example of a first class would be a seesaw, an example of a second class would be a stapler, and an example of a third class lever would a fishing rod.