Newton's First Law
net force must act upon an object to cause a change in ___
motion
Inertia is ___ to change in motion
resistance
an object's mass directly affects how much ___ is needed to accelerate the object.
force
An action force is always ___ with a reaction force.
paired
for every action, there is an ___ and opposite reaction.
equal
an object at rest will ___ at rest unless acted upon by a nonzero net force
remain
Mass is the amount of ___ an object has
matter
Choose one.
more mass means (greater or less) acceleration.
less
If mass increases and force stays the same, acceleration ____
decreases
Choose one.
Every action there is an equal in (strength or direction) and opposite reaction.
strength
True or False?
if an object is not moving, it will not start moving until a net force acts on it.
True
Newton's First Law is also called the law of ___
inertia
size and ___ of a net force equals the mass times the acceleration.
direction
in order for forces to ___, they must act on the same object.
balance
Choose one.
Every action there is an equal and opposite reaction in (strength or direction).
direction
If there is a net force acting on an object, it will ___
accelerate
Choose one.
more mass means (greater or less) inertia
greater
acceleration equals:
net force รท mass
action-reaction forces (are or are not) balanced because they act on different objects.
are not
True or False?
When rowing a boat, you want to move forward by pushing the water backwards.
True
A puck is at rest on ice, but a hockey player hits it. what does this cause the puck to do?
accelerate
Helen has a 100 lbs dog on her lap. Julia has a 12 lbs dog on her lap. Which dog has less inertia?
Choose one.
Jimmy is pulling a wagon filled with apples. If he takes some apples out, he will have (greater or less) acceleration.
greater
a hockey player hits a puck with his stick, the action force is the force of the stick on the puck. The ___ force is the force of the puck on the stick.
reaction
True or False?
When walking you are moving yourself, there is no opposite force.
False, the ground is pushing you up as you push on the ground.