Mechanical Comprehension Flashcards
_____ can be defined as the capacity to do work.
Energy
The basic unit of work is the _____, and it represents _____.
joule (J); newtons times meters (or kg * m^2/s^2)
Identify the common name for this rule: An object at rest tends to stay at rest, and an object in motion tends to stay in motion at constant velocity unless acted on by an unbalanced force.
Newton’s first law of motion
What is the difference between mass and weight?
Mass is the amount of matter an object has, while weight is the amount of force exerted on the object’s mass by gravity.
As an object falls, its _____ energy is converted to _____ energy.
potential; kinetic
_____ energy is the energy possessed by a moving object.
Kinetic
Rewrite the formula for momentum in order to solve for mass.
m = p/v
What is the formula for work?
w = fd
work = force x displacement
What is inertia?
Inertia is the tendency of objects to resist changes in their motion.
Power is defined as _____ and measured in _____.
the rate at which work is performed; watts (or sometimes horsepower)
What is the formula used to express Newton’s law of universal gravitation?
Force of gravity = ((G)(mass 1)(mass 2)) / distance between objects^2
G is a constant equal to 6.67 * 10^-11
What is the formula for acceleration?
acceleration = change in velocity / change in time
The basic unit of force is the _____, which represents _____.
newton (N); the force required to accelerate 1 kg by 1 meter per second per second: kg * m/s^2
What is the definition of mass?
a measure of the total quantity of matter in an object
Variables are inversely proportional when an increase in the independent variable results in a(n) _____ in the dependent variable.
decrease
In science, the delta symbol (looks like a small triangle) represents _____.
change in a quantity
F = ma is the mathematical formula representing Newton’s _____.
second law of motion
Newton’s third law of motion states that _____.
for every action, there is an equal and opposite reaction
_____ energy derives from an object’s position, shape, or state, rather than from its motion.
Potential
In science, acceleration is often measured in _____.
meters per second per second, or m/s^2
What is the formula for power?
p = w/t
power = work divided by time
What is the formula for momentum?
p = mv, where p = momentum, m = mass, and v = velocity
Acceleration due to gravity is approximately _____ meters per second per second, not counting air resistance.
9.8
The term _____ refers to the total of various pushes and pulls acting on an object.
net force
What are the two types of mechanical energy?
kinetic energy and potential energy
In a wheel and axle arrangement, force is usually applied to the _______ wheel in order to move the ______ wheel. (Choose from either larger or smaller for each blank.)
larger; smaller
What is the formula for calculating torque?
torque = rF, where r represents the length of the lever arm of the object being turned, and F represents a force being applied perpendicularly to that lever arm.
How would you increase the mechanical advantage of a wheel and axle arrangement?
by increasing the ratio of the diameter of the large wheel to that of the small wheel
_____ is the common term for the force that opposes movement through air or liquid.
Drag
What is the formula for calculating pressure applied evenly to a surface?
P = F/A, where P represents pressure expressed in pound of force per square inch, F represents force in pounds, and A represents area in square inches.
What is the formula for calculating friction?
Force of friction = coefficient of static or kinetic friction times the normal for a surface exerts when an object presses against it.
Fluid pressure is also known as _____ pressure.
hydraulic
What unit is used to express kinetic or potential energy, and what does that unit represent?
the joule (J), which represents (kg * m^2)/s^2
What unit is used to express torque?
either the newton-meter or the foot-pound
What is the advantage of a pulley?
A pulley enables someone to lift an object while exerting downward, rather than upward, force.
What does torque measure?
How much a force is able to cause an object to rotate
Liquids are effective at transmitting force because they are difficult to _____.
compress