Physics - Forces 1

Question 1

What is a scalar quantity?

Answer 1

Something with magnitude only. e.g. speed, mass, time

Question 2

What is a vector quantity?

Answer 2

Something with both magnitude and direction. e.g. velocity, force, acceleration

Question 3

What is a contact force?

Answer 3

A force that occurs when two objects touch each other e.g. normal, tension, air resistance

Question 4

What is a non-contact force?

Answer 4

A force that doesn’t require two objects to touch each other e.g. magnetism, electrostatic forces, gravity

Question 5

What is Newtons third law?

Answer 5

Every action has an equal and opposite reaction

Question 6

What is the equation for weight?

Answer 6

Weight = mass x gravitational field strength

Question 7

What is an objects centre of mass?

Answer 7

Where all of an objects mass is said to act from

Question 8

What is a resultant force?

Answer 8

If two or more forces act on an object, they can be replaced with a single arrow

Question 9

What is a moment?

Answer 9

If a force causes an object to rotate then it has a turning effect. This is called a moment

Question 10

What is the equation for moments

Answer 10

Moments = Force x Distance

Question 11

What is the principal of moments?

Answer 11

If an object is balanced, then the sum of the clockwise moments equals the sum of the anti-clockwise moments

Question 12

What is a gear?

Answer 12

A device that transmits the rotational effects of forces from one place to another