Dynamics - 9th Grade BJU

Who first wrote about what causes motion?

• Aristotle

• Archimedes

• Galileo

• Newton

Which one(s) are the result of a contact force?

• A ball thrown into the air falls down to the ground

• Two magnets repel each other

• A wrecking ball breaks a building

• Static electricity makes your hair stand on end

What is the weakest fundamental force?

• weak nuclear

• strong nuclear

• electromagnetic

• gravitational

Which one(s) are the result of a field force?

• A hamburger patty is formed by hands pushing it flat

• Wind causes a plane to shake

• A truck pulls a car with a rope

• A ball rolls down a hill

Which demonstrates forces acting on a balanced system?

• A golf ball hit onto the green

• A crane lifting a heavy load

• a falling meteorite reaches terminal velocity

• A person hand-stirring cookie dough

Which object has the least inertia?

• a robin

• Mount St Helen's

• A brick of platinum

• the planet Jupiter

Which of these is a non-contact force?

• Friction

• Magnetic force

• Spring force

• Normal force

What is the unit of force in the International System of Units (SI)?

• Joule

• Newton

• Watt

• Pascal

The sum of all forces acting on an object and direction is called the

• Balanced Force

• Net Force

• Unbalanced Force

• Contact Force

Are the forces balanced or unbalanced?

• Balanced

• Unbalanced