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Physics
Name
Algebra Review
Block
15) A ball moving at 30 m/s has a momentum of 15 kg·m/s. The mass of the ball is —
Sheet #
In physics, each variable in an equation represents a real, measurable quantity. In physics, t represents time; d
represents distance; v represents velocity… you see? Each variable actually represents something that is
measurable in the real world. Your task now is to solve each of the following equations for the quantity named.
1) Solve the equation for “distance”… v =
2) Solve the equation for “time”… a =
d
t
Δv
t
8) Solve the equation for “distance”… W = F·d
16) What is the voltage in a battery that is connected to a copper wire that has a resistance of 8 ohms and
current of 2 amps?
17) A sample of an element has a volume of 78.0 mL and a density of 1.85 g/mL. What is the mass in
grams of the sample? Record and bubble in your answer to the nearest tenth on the answer document.
9) Solve the equation for “time”… P =
W
t
1 0) Solve the equation for “velocity”…
K = ½ mv 2
18) What is the efficiency of an air conditioner if there is a work input of 320 J and a work output of 80 J?
3) Solve the equation for “acceleration”… v = at
19) A block of maple wood with a volume of 405 cubic centimeters and a density of 0.67 g/cm3 is sawed in
half. The density of the two smaller blocks is now —
4 ) Solve the equation for “acceleration”… d = ½ at 2
5) Solve the equation for “mass”… p = mv
11) Solve for “output force”…
AMA =
12) Solve for “output distance”…
Fout
Fin
IMA =
d in
d out
20) What is the current in a copper wire that has a resistance of 2 ohms and is connected to a 9-volt
electrical source?
21) How much force is needed to accelerate a 1,300 kg car at a rate of 1.5 m/s2?
6) Solve the equation for “force”… I = Ft
1 3) Solve the equation for “length”…T = 2π
l
g
22) At 0°C sound travels through air at a speed of 330 m/s. If a sound wave is produced with a wavelength
of 0.10 m, what is the wave’s frequency?
7) Solve the equation for “height”…U = mgh
14) Solve the equation for “velocity”…
ac =
v2
r
Physics
Name
G.U.E.S.S. problem solving
Block
5) How far does a ship float in 25 hours, traveling at 110 km/h
Sheet #
PHYSICS PROBLEM-SOLVING… just G.U.E.S.S.
For word problems and all other problems solving exercises, you must use the following format:
6) If a 1000 kg moose has a momentum of 15,000 kg·mph, how fast is it moving?
1. Givens:
 Write down every piece of information given in the problem along with its symbol.
 Include a sketch and Free-Body Diagram, every time it is applicable.
2. Unknown
 Decide what question the problem is asking you to solve… answer the question that is asked!!!
3. Equations
 Base Equation - the standard form of a formula. Use the equation sheet to choose an appropriate base
7) My big, fat ugly neighbor Bob exerts a force of 50 N to a 25 kg box full of junk. What is the box’s
acceleration?
equation.
 Working Equation - base formula rearranged so the unknown is on the left and all other variables are on the
right.
4. Substitution
 Check to be sure all the information is in a consistent set of units.
 Plug-n-Chug… substitute the known values, with units, into the working equation.
8) Calculate the instantaneous speed of an apple that falls freely from a rest position and accelerates at
10 m/s2 for 1.5 sec.
5. Solution
 Make your calculations and check that each answer is in the proper units and boxed.
Physics problem-solving example:
How long will it take a car to travel 51 meters at an average speed of 17 meters per second?
Givens: distance (d) = 51 m
9) Traveling at an average speed of 15 m/s, how long will it take Snuggles to go 65 m?
and average velocity (vavg) = 17 m/s
Unknown: time (t) = ?
Equations… base equation: vavg =
working equation: t =
Substitution: t =
d
t
d
v avg
51 m
17 m/s
Solution: t = 3.0 s
Make sure that you have included units with your answer and boxed it.
10) Paco accelerates a bag of “goodies” at a rate of 4 m/s2 by exerting a force of 20 N on it. What is the
bag’s mass?
11) Driving down the highway at 100 km/h, you get stuck behind Granny Goslow and see your chance to
safely pass. If it takes you 2 seconds for you to reach a maximum speed of 140 km/h, what is your
acceleration?
1) Calculate the average speed (in m/s) of a cheetah that runs 140 meters in 5 seconds
12) How long does it take a go-cart, accelerating at a rate of 3 mph/s, to go 24 miles?
2) Calculate the acceleration of a car (in km/h*s) of a car that can go from rest to 100 km/h in 10s
13) Snuggles the cat travels 27 meters in 3 seconds. Find Snuggle’s rate of acceleration (assume it is
constant).
3) Calculate the mass of a box that is moving at 25 km/h with a momentum of 500 kg·km/h.
14) Snuggles is dragging a 30 kg crate full of cat nip. The crate accelerates at a rate of 3 m/s2. How much
force is Snuggles exerting on the crate?
4) Calculate the speed (in m/s) of a skateboarder who accelerates from rest for 3 sec. down a ramp at an
acceleration of 5m/s2
15) What is the momentum of a 15 kg ball that is moving at 25 m/s?