I like to move it
<Star Wars quote>
Isaac says...
Do your work
It's simple, really
100
What do we call the distance traveled divided by the time it takes to travel that distance? (p.130)
Average speed
Because average speed is calculated by dividing the distance by time, its units always will be a distance unit divided by a time unit. For example: m/s or km/hr
100
What do we call a "push or a pull" ? (p.136)
Force
100
What do we call the set of rules developed by Isaac Newton to explain how forces affect the motion of an object? (p.138)
Newton's Laws of Motion
100
What is it called when an applied force causes an object to move in the direction of the force? (p.145)
Work
100
What simple machine is made up of an object, like a wheel, that has a groove with a rope or cable running through it? (p.147)
Pulley
A pulley changes the direction of the input force.
200
What do we call the speed of an object at any instant of time? (p.131)
Instantaneous speed
When you ride in a car, the instantaneous speed is given by the speedometer
200
What is the SI unit of force? (p.136)
Force is measured in newtons (N)
200
Which of Newton's laws of motion states that an object will not change its motion unless an unbalanced force acts on it? (p.138)
Newton's first law of motion
200
True or false?
Effort always equals work. (p.144)
FALSE!
Work is done only when an object moves in the direction of the applied force.
200
What simple machine is made of a rod or a plank that pivots on a fixed point called a fulcrum? (p.148)
Lever
Levers can increase a force, or increase the distance over which the force is applied. The three types of levers depend on the positions of the input force, the output force, and the fulcrum.
300
If an object is moving, and the instantaneous speed does not change, what do we call that? (p.132)
Constant speed
300
True or false?
For an object's motion to change, a force must be applied to the object. (p.136)
TRUE!
The force applied causes the object to accelerate (speed up, slow down, or change directions)
300
What do we call the force that resists sliding motion between two touching surfaces? (p.139)
Friction
It always acts opposite the direction of the motion.
In general, the rougher the surfaces are, the greater the friction will be.
300
What is the formula for calculating work? (p.145)
work = force x distance
or w = Fd300
What simple machine is made of two round objects that are attached and rotate together about the same axis? (p.149)
Wheel and Axle
The mechanical advantage of the wheel and axle can be calculated by dividing the radius of the wheel by the radius of the axle
400
If you know the average speed traveled, and the amount of time spent traveling, what can you figure out? (p.132)
Distance
distance traveled = average speed x time
or d = st
400
What do we call the combination of all the forces acting on an object? (p.137)
Net force
400
What do we call the tendency of an object to resist a change in motion? (p.139)
Inertia
The more mass an object has, the greater its inertia.
400
What is the SI unit for work? (p.145)
Joules (J)
1J = to 1N x mass
400
What simple machine has a sloped surface, and is sometimes called a ramp? (p.149)
Inclined Plane
It allows you to lift a heavy load by using less force over a greater distance.
500
What do we call the speed of an object and its direction of travel? (p.133)
Velocity
Velocity changes when the speed changes, the direction changes, or both change.
500
If you push a box with 10N of force towards the right, and a friend pushes with 5N of force also to the right, what is the net force applied to the box?
10N right + 5N right = 15N right
If the forces are in the same direction, add them together to form the net force.
500
Which law states that if an object is acted upon by a net force, the acceleration of the object will be in the direction of the net force? (p.140)
Newton's second law of motion
According to the second law of motion, acceleration can be calculated by dividing net force by mass.
acceleration = net force รท mass
500
Machines are devices that make work easier. What do you call a machine that uses only one movement? (p.146)
Simple machine
A machine that is a combination of simple machines is called a compound machine (example: a can opener combines several simple machines)500
What simple machine is a moving inclined plane with one or two sloping sides? (p.150)
Wedge
A wedge can change the direction of the input force
600
What is calculated by dividing the change in velocity by the amount of time needed for that change to occur? (p.133)
Acceleration
The SI unit for acceleration is m/s2, which is the result of dividing the units m/s by the unit s.
600
If you pull a door with 10N of force to the right, and a friend is pulling on the left side of the door with 7N of force, what is the net force?
10N right - 7N left = 3N right
If two forces are in opposite directions, the net force is the difference between the two forces, and is in the direction of the greater force
600
Which law of motion states that when one object exerts a force on a second object, the second object exerts an equal force in the opposite direction on the first object? (p.141)
Newton's third law of motion
The force exerted by the first object is the action force. The force exerted by the second object is the reaction force.
600
What do we call the number of times that an applied force is increased by a machine? (p.146)
Mechanical advantage
600
What simple machine is an inclined plane that has been wrapped around a cylinder post? (p.150)
Screw
