Physics and Math Flashcards
When rounding decimals for multiplication and division , what direction do you round?
multiplication: numbers in opposite directions
division: both numbers in the same direction
What are the rules for significant figures?
1) Count all numbers between the first nonzero digit on the left and the last nonzero digit on the right
2) Any zeroes to the left of the first nonzero digit are not significant
3) If there are zeroes to the right of the last nonzero digit and there is a decimal point in the number, then those zeroes are significant. If there is no decimal point then they are not significant (3,490: 3, 3,490.0: 5)
4) For measurements, the last digit is an estimation and is not significant
Exponent rule: what is any number to the zeroth power?
X^0 = 1
Exponent rule: multiplication (same base number)
X^A x X^B = X^(A+B)
Exponent rule: division (same base number)
X^A / X^B = X^(A-B)
Exponent rule: raised to two powers
(X^A)^B = X^(AxB)
conversion on log to ln
logx = lnx/2.303
What is the kinetic energy equation?
K = 1/2mv^2 m = mass in kilograms v = speed in meters per second
What is the gravitational potential energy equation?
U = mgh U = potential energy m = mass in kilograms g = acceleration due to gravity (9.8 m/s^2) h = the height of the object
What is the elastic potential energy equation?
U = 1/2kx^2 U = potential energy k = the spring constant x = the magnitude of displacement from equilibrium
What is total mechanical energy and its equation?
total mechanical energy is the sum of an object’s potential and kinetic energies
E = U + K U = potential energy K = kinetic energy
What is the equation for work?
W = F x d = Fdcos(theta) W = work F = the magnitude of the applied force d = the magnitude of the displacement through which the force is applied theta = the angle between the applied force vector and the displacement vector
How do you calculate work for processes in which pressure remains constant?
W = P x deltaV
What is the equation for power?
P = W/t = deltaE/t P = power W = work (which is equal to deltaE, the change in energy) t = the time over which work is done
What is the work-energy theorem equation?
Wnet = deltaK = Kf - Ki
What is mechanical advantage and its equation?
mechanical advantage is the ratio of magnitudes of the force exerted on an object by a simple machine (Fout) to the force actually applied on the simple machine (Fin)
mechanical advantage = Fout/Fin
What is the equation for efficiency?
efficiency = Wout/Win = (load)(load distance)/(effort)(effort distance)
What is the equation for Fahrenheit to Celsius?
F = 9/5C + 32
What is the equation for Kelvin to Celsius?
K = C + 273
What is the zeroth law of thermodynamics?
when two objects are both in thermal equilibrium with a third object, they are in thermal equilibrium with each other. By extension, no heat flows between two objects in thermal equilibrium
How do the initial length of an object and the amount it expands for a given temperature change relate to one another?
Expansion is a result of an increase in dimension at all points along an object. If an object is initially longer, it will experience a greater expansion. This is also represented in the formula for thermal expansion because there is a direct relationship between length change and the initial length of the object.
Can a closed system transfer matter? Energy?
it cannot transfer matter but it can transfer energy
Can an isolated system transfer matter? Energy?
it cannot transfer matter nor energy
Can an open system transfer matter? Energy?
it can transfer both matter and energy