Download Applied Physics Test Bank: Mechanics, Vectors, and Motion and more Exams Physics in PDF only on Docsity!
Test Bank For
Applied Physics, 12th Edition by Dale Ewen Neill Schurter P Erik Gundersen
Chapter 1 - 24
Chapter 1 The Physics Tool Kit
- The metric prefix for 0.010 is ________.
Answer: centi
- The metric symbol, or abbreviation, for milli is ________.
Answer: m
Write the following number(s) in scientific notation:
Answer: 4.5 × 10
Answer: 7.42 × 10
Write the following number in decimal form:
5) 3.28 × 10
Answer: 0.
6) 2.65 × 10
Answer: 265,000,
Fill in each blank: (Round to three significant digits when necessary.)
- 1.2 km = ________ m
Answer: 1200
- 6.9 L = ________ ml
Answer: 6900
- 750 μm = ________ mm
Answer: 0.
- 670 mm
= ________ cm
Answer: 6.
- 6500 cm
= ________ m
Answer: 0.
- 15 kg = ________ lb
Answer: 166
- 96 in. = ________ yd
Answer: 2.
- 15 ft
= ________ m
Answer: 0.
Determine the accuracy (the number of significant digits) in each measurement:
- 20,900 m
Answer: 3
- 0.04060 s
Answer: 4
17) 3.6 × 10
km
Answer: 2
Determine the precision of each measurement:
- 23.9 m
Answer: 0.1 m
- 14,050 ft
Answer: 10 ft
20) 5.0 × 10
s
Answer: 1000 s
- Use the rules of measurement to add 18.5 m; 2070 cm; 95.25 cm; 0.045 m.
Answer: 40.2 m
- Find the area of a rectangle 22.6 m long and 4.60 m wide.
Answer: 104 m
- Find the volume of a rectangular box 18.0 cm long, 9.0 cm wide, and 6.00 cm high.
Answer: 970 cm
Express each of the following values using scientific notation:
- 0.0001042 mi.
Answer: 1.042 × 10
mi
- 6,800,000 in.
Answer: 6.8 × 10
in.
Applied Physics, 12e (Ewen/Schurter/Gunderson)
Chapter 2 Problem Solving
- What is the difference between a subscript and an exponent?
Answer: An exponent is a mathematical operation. A subscript is used to define a variable a
specific feature or component of a variable.
- What is the difference between a formula and a working equation?
Answer: A formula is a basic equation, usually expressed in letters and numbers. A working
equation is created when the desired variable is isolated on one side of the equation.
- What is the purpose of estimation when problem solving?
Answer: Estimating the expected answer in problem solving can serve as a check to make sure
the answer is correct.
- Solve for m in the formula F = ma.
Answer: m = F/a
- Solve for t in the formula s = 1/2 (v f
)t.
Answer: t = 2s / (v f
- Solve for v f
in the formula s = 1/2 (v f
)t.
Answer: v f
= (2s/t) - v i
- Solve for h in PE = mgh.
Answer: h = PE / mg
- Given V= πr
h, if r = 5.0 cm and V = 250 cm
, what is h?
Answer: h = 3.2 cm
- Given A = 1/2 bh, if b = 10.0 cm and h = 12.2 cm, what is A?
Answer: A = 61.0 cm
- A cone has a volume of 315 cm
and a radius of 7.50 cm. What is its height?
Answer: h = 5.35 cm
- A right triangle has a side of 82.4 mm and a side of 19.6 mm. Find the length of the
hypotenuse.
Answer: 84.7 mm
- Given a cylinder with a radius of 14.4 cm and a height of 16.8 cm, find the lateral surface area.
Answer: 1520 cm
- A rectangle has a perimeter of 80.0 cm. One side has a length of 28.0 cm. What is the length of
the adjacent side?
Answer: 12.0 cm
- The formula for the volume of a cylinder is V = πr
h. If V = 4520 m
and h = 36.0 m, find r.
Answer: r = 6.32 m
- The formula for the area of a triangle is A = 1/2 bh. If b = 3.12 m and A = 82.6 m
, find h.
Answer: h = 52.9 m
- A rectangular parking lot measures 80.0 m by 75.0 m. If the parking lot needs three sections
that each measure 8.00 m by 8.00 m for tree plantings, how much area is left for parking spaces?
Answer: A = 5810 m
Applied Physics, 12e (Ewen/Schurter/Gunderson)
Chapter 3 Vectors
- Explain the difference between a scalar and a vector quantity.
Answer: Scalar is a quantity that specifies magnitude. Vector is a quantity that specifies both
magnitude and direction.
- Explain the difference between distance and displacement.
Answer: Distance is a scalar that specifies the magnitude or the amount that an object has
changed its position. Displacement is a vector that specifies the direct distance and direction that
an object has moved.
- Using a scale of 1.0 cm = 25 km, find the length of the vector that represents a displacement of
450 km.
Answer: 18 cm
Use graph paper to find the resultant of each set of displacements in the following problem(s).
- 45 km due east, then 45 km due north, and then 45 km due east.
Answer: 100 km at 27° north of east
- 85 km due south, then 25 km 45° south of east, then 45 km due east, and then 45 km at 25° north
of east.
Answer: 130 km at 38° south of east
Use a calculator to find each trigonometric ratio rounded to four significant figures in the
following problem(s).
- sin 18.5°
Answer: 0.
- tan 67.25°
Answer: 2.
- cos A = 0.
Answer: 32.2°
- A right triangle has legs of 24.0 cm and 36.0 cm. Find the length of the hypotenuse.
Answer: 43.3 cm
- A right triangle has a hypotenuse with length of 85.0 cm and one leg with 55.5 m. Find the
length of the other leg.
Answer: 64.4 m
- A right triangle has one acute angle that measures 34.5°. What is the measure of the other acute
angle?
Answer: 55.5°
- An antenna is attached to a vertical pole. If a guy wire is attached 40.0 ft from the bottom of the
pole and to an anchor on level ground 25.0 ft from the base, what angle does the guy wire make
with level ground?
Answer: 58.0°
- A conveyor is used to lift grain to a bin. The angle of elevation of the conveyor is 48.5°. If the
grain is elevated 15.0 m, how long is the conveyor?
Answer: 20.0 m
- Find the x- and y-components of the resultant vector R and graph the resultant vector R.
Vector x-component y-component
A +4 - 6
B - 6 - 3
C - 5 +
D - 1 +
Answer: R x
= - 8; R
y
- Find the x- and y-components of the vector v = 45.0 m/s at 205.0° in standard position.
Answer: v x
= - 40.8 m/s; v y
= - 19.0 m/s
Applied Physics, 12e (Ewen/Schurter/Gunderson)
Chapter 4 Motion
- While driving at 75 km/h, how far can you travel in 1.25 h?
Answer: 94 km
- If Grandma lives 225 km away, how long will it take to drive to her house if you average 95
km/h?
Answer: 2.7 h
- A trucker drove from San Francisco to Washington, DC (2865 mi). The entire trip required 77 h
and 30 min. If 16 h and 30 min of that time was spent sleeping and 3 h 40 min was used for meals
and refueling, what was the average speed while on the road?
Answer: 5 mi/h
Change 95.0 km/h to the speed units given in the following problem(s):
- m/s
Answer: 26.4 m/s
- mi/h
Answer: 59.0 mi/h
- ft/s
Answer: 86.6 ft/s
- A sports car accelerates from a standing start to 65 mi/h in 4.61 s.
a. Find its acceleration in ft/s
b. How far can it travel in that time?
Answer: (a) 21 ft/s2 (b) 230 ft
- A motorcycle traveling at 45.0 mi/h accelerates to 60.0 mi/h in 5.00 s.
a. Find its acceleration in ft/s
b. How far can it travel in that time?
Answer: (a) 4.40 ft/s
(b) 385 ft
- An airplane can average 450 mi/h with enough fuel for a flight of 3.5 h. How far can it travel?
Answer: 1600 mi
- An archer shoots an arrow into a piece of wood. The arrow is traveling at 120 km/h when it
strikes the wood. The arrow penetrates 3.8 cm into the wood before stopping. What is its average
acceleration (in m/s
into the wood?
Answer: - 15,000 m/s
acceleration change during the ball's flight.
Answer: There is no horizontal acceleration during the flight. The vertical acceleration (the
acceleration due to gravity) remains a constant downward 9.80 m/s
throughout the flight.
- A cannon launches a cannonball horizontally off a cliff that is 25.5 m high. If the cannonball is
fired with a velocity of 28.3 m/s, how far from the edge of the cliff will the ball land?
Answer: 64.5 m
- A cannon at ground level launches a cannonball horizontally. If the cannon fires with a
velocity of 28.3 m/s and at an angle of 30°, how far will the cannon ball travel?
Answer: 71.1 m
- Explain what happens to the range of projectiles as the angle of launching changes from 0° to
45°. What happens to the range of projectiles as the angle of launch changes from 45° to 90°?
Answer: range increases; range decreases
Applied Physics, 12e (Ewen/Schurter/Gunderson)
Chapter 5 Force
- Explain inertia.
Answer: Inertia is the property of a body that causes it to resist a change in its motion. Inertia is
defined by the object's mass.
- What is the difference between mass and weight?
Answer: Mass is a measurement of inertia of a body. Weight a vector that represents the amount
of force that gravity applies to the mass.
- Find the acceleration produced by a total force of 165 N on a mass of 4.50 kg.
Answer: 36.7 m/s
- Find the force necessary to give a 1750-kg car an acceleration of 11.0 m/s
Answer: 19,300 N
- Explain the difference between starting friction and sliding friction. Which has a greater
coefficient of friction?
Answer: Starting friction is the force that attempts to prevent a stationary object from sliding.
Sliding friction is the force that resists the continuation of the object's movement. Starting friction
tends to have a higher coefficient of friction.
6 ) A wooden crate is dragged across a concrete floor. What are two things that can be done to
decrease the coefficient of friction between these two surfaces?
Answer: Lubricate the area between the two surfaces. Place rollers or ball bearings between the
two surfaces. Rolling friction can be significantly lower than sliding friction.
- The coefficient of sliding friction on concrete is 0.30. What weight of steel can be pulled across
a concrete floor by a winch with a 450 lb capacity?
Answer: 1500 lb
8 ) A sled weighing 3350 N is pulled over snow at uniform speed by exerting a force of 1200 N.
Find the coefficient of friction.
Answer: 0.
- Find the net force including its direction of the following: 175 N to the left; 234 N to the right;
75 N to the right; 225 N to the left; 45 N to the right.
Answer: 37 N to the left
- A cyclist and her bicycle have a combined mass of 75.0 kg. If the frictional force acting against
the motion of the bicycle is - 23.5 N, what force must the cyclist apply to maintain a constant
velocity?
Answer: 23.5 N resulting in a net force of 0 N
- Provide a non-mathematical definition for momentum.
Answer: Momentum is a measure of the amount of inertia and motion an object has or the
difficulty in bringing a moving object to rest.
- Which object has a greater momentum, a stationary tractor-trailer or a tossed tennis ball?
Explain your answer.
Answer: The tossed tennis ball has greater momentum because it has both mass and motion.
- Find the momentum of a tennis ball of mass 60.0 g served with velocity 65.0 m/s.
Answer: 3.90 kg m/s
- Explain how a tennis racket can apply an impulse to the tennis ball.
Answer: The tennis racket applies a force for a period of time. The impulse alters the ball's
velocity, thereby also changing its momentum.
- If a tennis racket strikes a ball (m = 60.0 g; v = 65.0 m/s) for a period of what force does the
tennis racket apply to the ball? What is the impulse of this interaction?
Answer: 53.8 N; 3.90 N s
- Find the mass of a projectile when fired at 275 m/s if it is to have the same momentum as a
145 - g projectile fired at 325 m/s.
Answer: 171 g
- Using the concept of impulse, explain the benefits of "crumple zones" in automobile collisions.
Answer: "Crumple zones" are used to increase the amount of time of a collision, thus reducing
the amount of force experienced by the automobile and the passengers.
- Why does a bouncing ball experience a greater impulse than a ball that strikes the surface and
stops?
Answer: A bouncing motion results in a larger change in velocity, thereby resulting in a greater
change in momentum and impulse. A ball that simply strikes a surface and stops experiences a
much smaller change in velocity and therefore smaller change in momentum and impulse.
- Explain the difference between elastic and inelastic collisions.
Answer: Inelastic collisions result in two or more objects being coupled together after the
collision. Elastic collisions result in two or more objects bouncing off one another and returning to
their original shapes.
- Provide an example of an elastic collision and an inelastic collision.
Answer: Elastic collision—two billiard balls, bowling ball and pins, tennis ball and racket.
Inelastic collision—automobiles locking together, train cars coupling together, baseball player
catching a ball in a glove.
Use the following information to answer the question(s) below:
A person is driving an automobile at 95.0 km/h and throws a bottle of mass 0.600 kg straight out
the window. (Assume there is no air resistance.)
- With what momentum does the bottle hit a roadway sign?
Answer: 15.8 kg m/s
- With what momentum does the bottle hit an oncoming automobile traveling in the opposite
direction at 85.0 km/h?
Answer: 30.0 kg m/s
- With what momentum does the bottle hit an automobile passing and traveling in the same
direction at 115.0 km/h?
Answer: 3 .33 kg m/s
Applied Physics, 12e (Ewen/Schurter/Gunderson)
Chapter 7 Concurrent and Parallel Forces
- Find the sum of the following set of forces acting on the same point in a straight line:
745 N (right); 372 N (left); 427 N (left); 555 N (left); 965 N (right).
Answer: 356 N (right)
- Forces of 348 N and 295 N act on the same point.
a. What is the magnitude of the maximum net force the two forces can exert together?
b. What is the magnitude of the minimum net force the two forces can exert together?
Answer: (a) 643 N (b) 53 N
- Forces of F 1
= 975 N, and F 2
= 745 N, and F 3
= 1175 N are applied to the same point. The
angle between F 1
and F 2
is 60.0°. The angle between F 2
and F 3
is 30.0°. F 2
is between F 1
and
F
. Find the resultant force.
Answer: 2260 N at 53.5° from F 1
- Three forces, each of magnitude 1450 lb act on the same point. The angle between adjacent
forces is 45.0°. Find the resultant force.
Answer: 3500 N at 45.0° from F 1
- A given wire can support 4550 lb before it breaks. How many 575 lb weights can it support
without breaking?
Answer: 7
- Find the tension in the cable and the compression in the support of the sign shown below.
Answer: T = 3230 N; C = 2650 N
- Find the tension in each cable.
Answer: T 1
= 24,900 N; T
= 10,300 N
- Determine the tension "T" of the cable and the compression "C" on the boom assembly of the
crane.
Answer: T = 3759 N; C = 5064 N
- The first condition of equilibrium states that
Applied Physics, 12e (Ewen/Schurter/Gunderson)
Chapter 8 Work and Energy
- Find the work done by a person pulling a wagon containing 60.0 lb of bricks across 36.0 ft of
level floor by exerting a constant force of 21.0 lb.
Answer: 756 ft lb
- How much work (in ft lb) is done by a large bucket that can lift 4.5 tons of dirt 14 ft into the air
and dump it into a 5.0 yd
dump truck?
Answer: 130,000 ft lb
- A mechanical lift raises a 325 kg automobile 2.00 m for servicing. How much work was done by
the lift?
Answer: 6370 N m
- A pallet is pulled 125 m across a floor by a cable that makes an angle of 45° with the floor. If
1150 N is exerted on the cable, how much work is done?
Answer: 102,000 N m
- How much power is required to lift a 575 lb weight 30.0 ft in 4.00 s?
Answer: 4310 ft lb/s
- How much power is required to lift a 225 kg body 15.0 m in 5.00 s?
Answer: 6620 W or 6.62 kW
- How much time is required to lift a 1275 lb object 45.0 ft with a motor that produces 15.0 hp?
Answer: 6.95 s
- How much time is required to lift a 525 kg object 25.0 m with a motor that produces 2.50 kW?
Answer: 51.5 s
- What maximum mass can be lifted 45.0 m in 1.00 min by a 1.50 kW motor?
Answer: 204 kg
- A pump is capable of developing 5.0 kW of power. How many liters of water per minute can
be lifted a distance of 25 m? (1 L of water has a mass of 1 kg.)
Answer: 1200 L/min
- Find the potential energy of a 1250 lb counter balance in an elevator that is raised 45.0 ft from
its lowest point.
Answer: 56,300 ft lb
- Find the kinetic energy of a 310 kg wrecking ball moving at 4.0 m/s.
Answer: 2500 J or 2.5 kJ
- Find the kinetic energy of a 5.0 ton truck traveling at 65 mi/h.
Answer: 140,000 ft lb
- Water is pumped at the rate of 275 m
/min from a lake into a tank on a hill 75.0 m above the
lake. (1 m
= 1000 L)
a. What power (in kW) must be delivered by the pump?
b. What horsepower rating must this pump motor have?
c. What is the increase in potential energy of the water each minute?
d. Assuming 25% of the pump power is lost, what power (in kW) must be delivered by the pump?
Answer: (a) 3370 kW (b) 4520 hp (c) 202 MJ (d) 4210 kW
- A pile driver weighs 975 lb and falls from a height of 45.0 ft. Find its velocity as it hits the pile.
Answer: 53.8 ft/s
- A 55.0 g bullet is fired vertically with an initial velocity of 123 m/s.
a. What is its velocity at its highest point of travel?
b. What maximum height does it reach?
c. At what velocity does it hit the ground?
Answer: (a) 0 (b) 797 m (c) 125 m/s
- A 2.00 lb rock is dropped from a bridge to the water 50.0 ft below.
a. What is its velocity as it hits the water?
b. How long does it take to hit the water?
c. What is its kinetic energy as it hits the water?
Answer: (a) 56.7 ft/s (b) 1.76 s (c) 99.8 ft lb
- A 2.50 N rock is thrown downward from a cliff at 10.0 m/s.
a. What is its velocity after falling 25.0 m?
b. What is its velocity as it hits the water 125 m below?
c. What is its kinetic energy as it hits the water?
Answer: (a) 24.3 m/s (b) 50.5 m/s (c) 325 J
- A farmer lifts a dozen 10 lb sacks of grain from the ground to the bed of his truck 3.50 ft above
the ground. What is the total work done?
Answer: W = 420 ft lb
- A 1.0 ton beam is raised 35 ft in 2.0 minutes.
a. How much work was done?
b. How much power (in horsepower) did it take?
Answer: (a) 7,000 ft lb (b) P = 1.1 hp
- An electric motor running on a 12 volt receptacle is drawing 8.00 Amps of current. What is the
motor's power? Express your answer in both watts and horsepower.
Answer: P = 96 W; P = 1.29 hp
Applied Physics, 12e (Ewen/Schurter/Gunderson)
Chapter 9 Rotational Motion
- Convert 15.0 revolutions to (a) radians and (b) degrees.
gear revolves at 80.0 rpm. How many teeth does the second gear have?
Answer: 30 teeth
- One gear with thirteen teeth rotates at 115 rpm and turns a second gear with 26 teeth. Find the
rpm of the second gear.
Answer: 57.5 rpm
- A gear train has 9 shafts. Do the first and last gears rotate in the same direction?
Answer: Yes
- A pulley of diameter 15.0 cm is driven by a motor and revolves at 10 rpm. The pulley drives a
second pulley with diameter 10.0 cm. Find the rpm of the second pulley.
Answer: 15 rpm
- A pulley with diameter 5.00 cm rotates at 10 rpm. Find the diameter of the second pulley if it is
driven at 25 rpm by the first.
Answer: 2.00 cm
- How does the presence of an idler gear affect the relationship between a driver gear and a
driven gear in a gear train?
Answer: An idler allows both gears to rotate in the same direction.
- When the number of shafts in a gear train is four, do the first and last gears rotate in the same or
opposite direction?
Answer: Opposite
- Why may a gear that is both a driver gear and a driven gear be omitted from a computation?
Answer: Since the gears are connected, they both rotate together.
Applied Physics, 12e (Ewen/Schurter/Gunderson)
Chapter 10 Simple Machines
- What is the purpose of using simple machines?
Answer: Simple machines result in useful work. Simple machines are typically used to reduce the
amount of effort force that is needed to do work.
- If more than one simple machine is used in a mechanism, it is called a complex machine.
Provide three examples of complex machines.
Answer: Pencil sharpener, bicycle, snow blower, can opener, automobile
- Define efficiency for a simple machine.
Answer: The ratio of work output of a machine to the work input of a machine.
- Is it possible to have a 100% efficient machine? Explain.
Answer: No. The work input to a machine is partially used to overcome internal friction within
the machine.
- A sport fisherman catches a swordfish on his fishing pole. What class lever is the fishing pole if
the end of the pole is positioned in a fixed fulcrum? Will the fishing pole have a mechanical
advantage greater or less than 1.00?
Answer: Third Class Lever; MA < 1.
- With respect to simple machines, explain why trucks and buses have larger steering wheels than
sports cars.
Answer: An increased radius provides the wheel and axle with a greater mechanical advantage.
Such an advantage is needed for a massive truck.
- A mechanic lifts the front of a car with a jack. Find the mechanical advantage if a force of on the
jack handle lifts the car that weighs 96 lb.
Answer: 32 : 1
- A mechanic lifts the front of a car with a jack. A force of 30.0 lb on the jack handle lifts a car that
weighs 960 lb. What could be done to the jack to increase its mechanical advantage?
Answer: Increase the length of the handle or increase the effort force.
- A worker exerts 85.0 lb on a lever to lift a weight. The distance from the worker to the fulcrum
is 8.00 ft; the distance from the weight to the fulcrum is 2.00 ft. Find the weight lifted. Find the
mechanical advantage of the lever.
Answer: 34 lb; 4.00:
- A worker uses a wheelbarrow to haul 225 lb of brick. The handles are located 4.00 ft from the
axle; the center of the load is 1.50 ft from the axle. How much upward force does the worker exert
to lift the handles of the wheelbarrow?
Answer: 84.4 lb
