Forces

A group of students is playing tug of war. They are both pulling with equal force and the rope isn't moving. This is an example of

• unbalanced forces

• balanced forces

• acceleration

• displacement

A firefighter feels the hose push backwards onto him as he uses it to put out a fire. Why?

• The hose material is very elastic

• Since the hose is at rest, it tends to stay at rest

• The force exerted on the water equals the mass of the water times its acceleration

• The escaping water exerts an equal and opposite force on the hose

Which is measured in Newtons?

• weight

• momentum

• inertia

• acceleration

The upward force on an object falling through the air is

• air resistance

• momentum

• inertia

• gravity

In station demos, when the block moved down the book cover, it moved with

• sliding friction

• rolling friction

• static friction

• fluid friction

the size of the gravitational force between two objects depends on their

• frictional forces

• inertia

• masses and the distance between them

• speed and direction

If you could travel to another planet, based on Law of Universal Gravitation, your weight on the new planet will be greater than your weight here on Earth if

• the new planet has less gravity than Earth

• The new planet has the same gravity as Earth

• the new planet has more gravity than Earth

• The gravity of the planet doesn't matter. Weight is the same everywhere.

"To every action there is an equal and opposite reaction" describes which law?

• Law of Conservation of Momentum

• Newton's 1st Law of Motion

• Newton's 2nd Law of Motion

• Newton's 3rd Law of Motion

Calculate the force on an object that has a mass of 10 kg and an acceleration of 4 m/sec². Remember F = ma

• 40 N

• 8N

• 2.5 N

• 0..4 N

A 500 N force is applied to a 25 m/sec² object. The mass of the object is... (F=ma)

• 12,500 m/s

• 12,500 kg

• 20 m/s

• 20 kg