Forces and Interactons Flashcards
Friction
Resistance cause by any two objects in contact
Unbalanced forces
Forces that cause a change in motion of an object
Balanced forces
Equal forces acting on an object in opposite directions
Newton’s first law of motion
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Newton’s Second Law of Motion
The acceleration of an object depends upon two variables - the net force acting upon the object and the mass of the object.
Newton’s third law of motion
For every action, there is an equal and opposite reaction
Inertia
The tendency of an object to resist a change in motion.
Force
A push or a pull, labeled in newtons.
Mass
The amount of matter in an object.
Acceleration
Rate of change in velocity, labeled m/s 2
Contact forces
Puses and pulls that result from direct touching of objects (friction, air resistance, and physical contact wit an object)
Non-contact forces
Pushes or pulls that result without the direct touching of objects acting at a distance (gravity and magnetism)
Gravity
A force of attraction between objects that is due to their masses.
Forces that cause a change in the motion of an object are called ____________________ forces.
Unbalanced
Equal forces acting on an object in opposite directions are called _________________ forces.
Balanced
Is this Newton’s 1st, 2nd, or 3rd law?
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force is known as which Law of Motion?
1st law
The tendency of an object to resist a change in motion: ____________________is described in which Law of Motion?
Inertia, 1st law
Which law describes the relationship between force, mass, and acceleration?
2nd law
Which law describes why we fly forward when a vehicle suddenly stops?
1st law
When the engines in a rocket ignite, the rocket lifts off. Which law describes why this happens?
3rd law
It is easier to push a small child on a swing than it is to push a larger child. Which Newton explains this phenomenon in which Law?
2nd law
Which Newton’s Law explains the phenomenon in a a Newton’s Cradle when two balls collide they cause two balls on the opposite end to move?
3rd law
As I stand on the ground, I push the ground with a force of 200 N, in turn, the ground pushes me with a force of _____ N.
200
If I place a bowling ball in the center of the classroom, it WILL not move unless a force acts upon it. Which term BEST explains this phenomenon? _______________________________
Inertia
A 12th grader and a 2nd grader are pulling back and forth fighting over a basketball. The 12 grader wins. This is an example of________________________ forces.
Unblanced
If the mass is the SAME, a GREATER force will cause LESS acceleration
True False
False
- If you push an object, that object pushes back in the opposite direction equally hard.
True False
True
- Forces always act in pairs True False
True
- To slow an object down, you need an applied force in the opposite direction. True False
True
- Action force = bowling ball hitting pins, the reaction force = pins flying in all directions. True False
False
- When force is held constant, an object of greater mass will accelerate faster. True False
True
Solve the following problems. The formulas have been provided for you. You MAY use a calculator. Be sure to label your answers!
-Calculating Force (Label your answers with N for Newtons.
A 1250 kg car accelerates at a rate of 5.0 m/s2.
How much force is the car’s engine producing?
(Force = Mass x Acceleration)
F = ma
F = 1250 x 5
F = 6250 N
Calculating Acceleration (Label your answers with a m/s2 for Acceleration)
What is the acceleration of a 400 g marble
that is being pushed with a force of 2 N?
(Acceleration = Force / Mass)
a = f/m
a = 2/400
F = 0.005 m/s 2
What is the formula for net force?
-Subtract the highest number to the lowest number
- Whichever is te highest number at the end, is te direction it is going in.
