Motion
What is the difference between speed and velocity?
Velocity includes a direction
What is the definition of a force?
It is a push or a pull
The equation for work
work = fd
What 2 things make up mechanical energy?
Kinetic and potential energy
Can the total mechanical energy increase of an object? How?
If you do work on that object.
What is the equation to calculate acceleration?
af-ai/t
The force acting right is 5N and the force acting left is 10 N. We call these _________forces
Unbalanced forces / Net force
What are 2 ways machines helps us?
They change the input force, direction or the distance
The type of energy related to the motion of particles.
thermal energy
What is the action and reaction force when going around a turn while driving a car on a road?
action force: tire applies force on road
reaction force: road applies force on tire
What are 2 ways you can change acceleration?
Change speed, direction or speed and direction
What are 2 factors that affect friction?
The type of surface and how hard they press together.
Why is no machine 100% efficient?
some work is lost due to friction?
What does the law of conservation of energy state?
Energy is not created nor destroyed but transferred from one form to another.
If a velocity time graph has a negative slope what kind of acceleration would we expect?
negative acceleration
A positive diagonal slope on a velocity time graph represents what kind of acceleration?
Constant acceleration
Two objects exert gravity on each other. If object one has 2x the mass as object two, how does the force of gravity on them compare?
They have the same force of gravity.
A hockey stick is an example of what kind of lever?
3rd class lever
What energy transformations take place when you use a flashlight.
A bottle opener is an example of what kind of lever?
2nd class lever
15s
In newton's first law, an object will remain at rest unless acted on by nonzero net force. This is also called the LAW OF ___________
inertia
How does an incline plane make work easier for us?
Use less input force.
A dog has a kinetic energy of 40 J and mass of 20 kg. What is its velocity?
2m/s
A 1 kg ball and 2kg ball travel in opposite directions at 1m/s. If they hit eachother and stick together, what would be their new velocity?
0.33m/s