May the Force be with you
What is the term for the combination of all forces acting on an object?
Net Force
When will the speed of an object change?
When the net forces acting on that object are unbalanced.
What are the units for energy?
Joules (J)
What is the measure of how hard it is to stop a moving object?
Momentum
What is Newton's first name?
Isaac
What are the units for force?
Newtons (N)
What is the term for a change in velocity over time?
Acceleration
True or false - An object may have either kinetic or potential energy, but never both.
False. Objects may have both kinds of energy. Example?
What causes a ball rolling across a rug to stop?
Friction
What is the tendency of an object to resist a change in it's motion? Which law?
Inertia. Newton's first law.
Net Force = Applied Force - ?
Opposing Force
What are the units for speed?
m/s
What type of energy is gained by a 17N book that is lifted 2m above the floor? Be specific.
Gravitational potential energy. How much?
What are the units for momentum?
kg*m/s
Fill in the blank… "For every action there is an ________ reaction." Which law?
Equal and opposite. Newton's third law.
What type of force prevents a person from falling through a chair when they sit on it?
Normal Force
How can you calculate average velocity (think of the units)?
Distance/Time
Fill in the blank… "Kinetic energy is the energy an object has because of its _______"
Motion
What is the formula for momentum (think of the units)?
momentum (p) = mass (m) * velocity (v)
What equation is most commonly associated with Newton's second law?
Force (F) = mass (m) * acceleration (a)
Draw a diagram of an object being pushed along the floor and label all forces.
Forces (and direction) should include applied, opposing (friction), gravity, normal.
True or false - On a flat road, if I stop pedaling my bicycle, I can expect that it will accelerate?
True. Acceleration is a change in velocity over time - not just speeding up!
A 36kg object has a velocity of 2 m/s2. How much kinetic energy does the object have?
KE = 1/2(m)(v2) 1/2(36)(2*2) = 72J
True or false - If a sumo wrestler and a gymnast are both moving, the sumo wrestler will always have more momentum.
False. Momentum depends on both mass and velocity.
If 10N of net force are applied to an ball that has a mass of 40kg, what will be the acceleration of the ball?
a = F/m 10/40 = 0.25 m/s2