Terminal Velocity and Momentum

What happens when an object falls through a fluid?

• First, object accelerates due to force of gravity.

• As it speeds up, resistive force increase.

• Resultant force reaches zero when resistive forces balance force of gravity.

• Object will fall at steady speed, called its terminal velocity.

What is the acceleration near the Earth’s surface?

10m/s² due to gravity.

What is Newtons third law?

For every action there is an equal and opposite reaction. e.g. hen one object exerts a force on another, the other object exerts an equal force back.

What is momentum?

The product of mass and velocity.

What happens when the momentum of an object is greater?

The greater the force needed to stop the object.

What happens to the momentum of small and large masses at the same speed?

A large mass will have more momentum than a small mass.

What happens to the momentum of slower and faster object with the same mass?

A faster object will have more momentum than a slower object.

What is the equation for momentum, mass and velocity?

Momentum = Mass x Velocity

What happens to the momentum in a closed system?

Total momentum before an evet is equal to the total momentum after an event.

What happens to the momentum within rockets?

The momentum gained by the exhaust being expelled backwards is equal to the momentum gained by a rocket moving forwards.

What happens to the momentum within projectiles?

The recoil momentum of the gun is equal to the momentum of the bullet.

What are examples of conservations of momentum?

• Recoil.

• Explosion.

• Rocket propulsion.

• Collision.