Speed and Acceleration
Formula for calculating speed
Distance/time
Finish the phrase: "An object in motion stays in motion and...
an object at rest stays at rest unless acted on by an unbalanced force
the formula for Newton's 2nd Law
F=ma
Newton's 3rd Law states that...
every action has an equal and opposite reaction
A tennis ball is served, the tennis player on the other side of the net swings at the ball but misses. This law explains why the ball stays in motion until it hits the fence.
Newton's 1st Law
a change in a moving object's speed or direction
Acceleration
What forces cause a change in objects motion?
Unbalanced forces
What is the force acting a cart that weighs 10 kg and is moving with an acceleration of 2m/s/s?
20 m/s/s
Draw an example of Newton's 3rd Law.
(show dry-erase board)
Which of Newton's Laws take force into consideration?
all of them
Formula for calculating acceleration
Final speed-initial speed/ time
Define Inertia
Tendency to resist change in motion
If a force of 10N occurs on a mass of 2kg, what must be the acceleration? (remember to use appropriate units!)
"5 m/s/s"
Mrs. Wallace is going down the sidewalk on her skateboard; Mrs. Hierholzer decides to get on too. What will Mrs. Wallace have to do to keep the skateboard moving at the same velocity?
push with more force
distance travelled is a car is moving at a speed of 30 km/hr for 1.5 hr
45 km
Which of the following has the greatest inertia? Person Car Jet Train
train
Difference between mass and weight
Mass is the amount of matter and weight is the force acting on an object due to gravity.
Explain the action and reaction forces acting on a book resting on a table.
action force is the weight of book on table - reaction force is a force equal to the books weight pushing up from the table onto the book
Safety researchers are simulating a head on collision using crash test dummies to represent what happens to people. One of the dummies doesn't have a seat belt on. What happens to the crash test dummy without the seatbelt when the car hits the concrete barrier and why?
the dummy flies out the window because an object in motion wants to stay in motion
What is the accelerating of a car that is traveling a a constant speed of 30m/s?
Zero
Which would have a greater acceleration, a small car or a large car, if the same force is applied?
a small car
Why does a marble on the floor slow down and eventually stop rolling if Newton's 1st Law says an object in motion stays in motion?
friction