Physics Semester 1 Exam

Two ice skaters are initially at rest. The 78.2 kg male ice skater pushes his 48.5 kg female partner forward and away from his body with a velocity of 8.46 m/sec. What is the male skater's velocity as a result of the push? (HINT: momentum after collision formula)

-5.25 m/sec backwards

Determine the net force on the object below: (See physics photo album) #2.3

0 N; balanced

Convert 6.37 x 10^-2 in standard form.

0.0637

Gwennen rides her bicycle 2.4 kilometers up a steep hill in 8 minutes. Her speed is ____ kilometers per minute.

0.3

A child's toy rake is held so that its output arm is 0.75 meters. If the machanical advantage is 0.33, what is the input arm length?

0.44

The amount of mechanical kinetic energy possessed by a 0.25-kilogram ball rolling at a speed of 2.5 meters per second is ____ joules. (HINT: find kinetic energy)

0.78

Solve for the net force of the the free body diagram below. (See physics album) #2

0N; at rest

What is 6.5 m converted to inches? (hint: 39.37 inches = 1 meter)

255.9 in

A unit used to measure power is

Watt

Of the following objects, the one which has the most mass is: Select one: a. the Goodyear blimp. b. a silver dollar. c. a piece of notebook paper. d. a physics textbook.

a. The Goodyear Blimp

Of the following, which equation does NOT correctly represent a relationship between distance, time and speed? Select one: a. Distance equals speed multiplied by time. b. Speed equals time multiplied by distance. c. Time equals distance divided by speed. d. Speed equals distance divided by time.

b. Speed equals time multiplied by distance.

In which of the following is the metric unit paired with its correct abbreviation? Select one: a. gram / gm b. milliliter / mL c. kilogram / cg d. centimeter / km

b. milliliter / mL

All of the following examples of motion can be caused by a force EXCEPT a:

boat speeding down a lake at a constant speed of 100 km/hr

Jumping on a trampoline, Jeffrey can easily soar 6 feet into the air but can only jump 2 feet from the blacktop of the driveway basketball court because the:

court applies a larger impulse

The acceleration due to gravity is: a. 9.8 m/sec2 on Earth. b. signified by the letter g. c. a downward acceleration. d. All of the above

d. All of the above

The information gathered from experiments is called _________.

data

The term that best describes the motion of an object that is slowing down is:

deceleration

What is happening to the objet at point C? (Look at physics photo album to see photo)

deceleration

As the mass of an object increases, the acceleration of that object

decreases

If an object is slowing down, then one knows for certain that the momentum of the object is ________.

decreasing

A student hypothesized that the amount of sunlight a sunflower plant receives determines the number of sunflower seeds the plant produces. In her experiment, the number of seeds the plant produces is the:

dependent variable

If you know the distance traveled and the amount of time it took, speed may be calculated by:

dividing distance by time

If the stretching force on a spring is doubled, the length of the spring will be:

doubled

To calculate momentum:

multiply the mass of an object by its velocity.

When you are seated in a chair, the force exerted on you by the chair is in a perpendicular direction called the:

normal force

A factor that affects the behavior of a system is called a(n):

variable

When you throw a ball up in the air, it travels up and then stops instantaneously before falling back down. At the point where it stops and changes direction to fall back down its:

velocity is zero

Action and reaction force pairs occur

whether there is motion or not

Frank starts from a certain point and moves east towards Henry's house for 7 miles, then goes north for 5 miles, and then turns west for 3 miles. Using the graph below, what are the x-y coordinates for the resultant vector? ( See physics photo album)

(4,5) mi

If a spring is compressed a distance of 0.25 m with a force of -20 N, what is the value of the spring constant k?

- 80 N/m

An rubber band is stretched from its resting position a distance of 0.10 m. If the spring constant is k = - 2.5 N/m, what is the force being exerted on the rubber band?

-0.25 N

If the spring constant k of a pogo stick is -3500 N/m and the weight of the person on the pogo stick is 700 N, how much is the spring in the bottom of the pogo stick compressed?

- 0.2 m

A ball with a mass of 1 kilogram is moving in a straight line at the same speed as a ball with a mass of 10 kilograms. Both balls are brought to rest in 4.0 seconds. What is true of the force required to stop the balls?

. It takes less force to stop the 1 kilogram ball because it has less inertia.

How much force is needed to accelerate a 70 kg rider and her 200 kg motor scooter at 4 m/sec^2

1,080 N

Lifting a 70-kilogram barbell 2.0 meters above the floor increases its potential energy by about:

1,372 joules

Solve for the net force of the the free body diagram below. (See physics album) #1

3N; right

A wheelchair ramp is 9.906 m long and is 1.067 m tall. Find the mechanical advantage of the ramp

9.28

An automobile jack exerts force on 4,500 newtons to raise a car 0.25 meters. The amount of work done by the jack is ________ joules.

1.125 J

Jonah is pushing his younger sister, Jessica, on a swing. If Jessica weighs 350 kilograms, how much higher above the ground must Jonah push her to increase her potential energy by 5250 joules? (HINT: use potential energy formula and solve for height!)

1.5 meters

According to the United States Food and Drug Administration, the recommended daily requirement of protein is 44 grams. How many ounces of protein is this? (Convert)

1.55 oz

Talia pulls her younger in a wagon 30 meters to the top of a ramp 3 meters high. If the ramp is frictionless, the mechanical advantage of the ramp is:

10

The conversion factor for changing one unit of length to another in the metric system is a multiple of:

10

What braking force is needed to stop a 1,000-kilogram car moving at 10 m/sec in a time of 1 seconds? (Hint: impulse formula)

10,000 newtons

A machine is required to produce an output force of 600 newtons. If the machine has a mechanical advantage of 6, what input force must be applied to the machine?

100 N

Determine the net force on the object below: (See physics photo album) #3.3

12 N to the right

A ramp with a MA of 8 lifts objects to a height of 1.5 meters. How long is the ramp

12 m

Convert this number to STANDARD form: 0.0120 x 10^4

120

A 4-kg box is pushed across a level floor with a force of 60 N for 20 m. What is the total work done on the box?

1200 J

How many kilograms are in 30.4 lbs.?

13.8 kg

Convert 57.0 inches to centimeters.

144.78 cm

Doug rides a motorcycle at an average speed of 42 miles per hour for 3.6 hours. The distance he travels is about ____ miles.

150

A 2.2 kilogram crate is pulled by a 30-newton force over a distance of 5 meters. The work done by pulling the crate is _______ joules.

150 J

Calculate the work done to lift a barbell weighing 100 newtons a distance of 1.5 meters.

150 joules

The metric unit of power and is known as one Joule per second is called a simple machine.

False

I dropped a penny from the top of the front of the school and it takes 1.85 seconds to hit the ground. Calculate the velocity at impact in m/sec.

18.13 m/sec

Determine the resultant Force on the object below: (See physics photo album) #2.4

19 N down

Determine the net force on the object below: (See physics photo album) #1.3

19 N to the right

A bungee jumper falls off a tower and travels 2 seconds before the bungee cord starts to slow her down. What was her average velocity in free fall?

19.6 m/sec

A professional LPGA golfer walks at an average rate of 3.20 feet per second on the golf course. The amount of time required for her to walk from the tee to a green 612 feet away is:

191 seconds

Solve for the net force of the the free body diagram below. (See physics album) #4

1N; up

At which point is the speed the greatest? (See physics photo album for picture)

2

The diagram below represents a force acting at point P: (See physics photo album) The pair of forces that could represent x and y components of this force are:

2

The diagram below represents a box sliding down an incline: (See physics photo album) The force of friction acting on the box is directed toward:

2 (to the left)

A 10 meter long ramp has a MA of 5. What is the height of the ramp

2 m

A 2-kilogram piece of clay moving at 4 m/sec strikes and sticks to a second 4-kilogram piece of clay moving at 1 m/sec in the opposite direction. Calculate the speed of the combined piece of clay. (HINT: conservation of momentum formula)

2 m/sec

Toby glances at the speedometer on his bicycle as he begins to roll downhill. It indicates he is traveling at 12 miles per hour when he initially looks at it and 20 miles per hour 4 seconds later. His acceleration is: (HINT: find acceleration)

2 mph/sec.

A 0.0272 kg arrow is fired with a velocity of 87.3 m/sec from a bow. The initial speed is 0 m/sec. Find the impulse on the arrow. (HINT: remember that impulse = change in momentum, they just have different units)

2.37 mc048-3.jpg

A rake is held so that its input arm is 0.4 meters and its output arm is 1.0 meters. What is the mechaniccal advantage of the rake?

2.5

The length of a new pencil is closest to:

20 centimeters

What is the one missing force on the following object that should be in equilibrium? (See physics album) #2.2

2N; right

What is the one missing force on the following object that should be in equilibrium? (See physics album) #4.2

2N; right

A 120-m long ski lift carries skiers from a station at the foot of a slope to a second station 40 m above. What is the IMA of the lift?

3

At which point is the object traveling at 0 m/sec? (HINT: at rest) (See physics photo album for picture)

3

At which point is the speed the least? (See physics photo album for picture)

3

How many seconds are in a stopwatch showing 1 hour, 3 minutes, and 5 seconds?

3.785 sec

The speed of a cheetah running 300 yards in 10 seconds is:

30 yards per second

A machine with a mechanical advantage of 2.5 requires an input force of 120 newtons. What output force is produced by the machine?

300 N

A basketball player who is 61.19 kg jumps 0.5 meters vertically off of the floor. What is her potential energy the instant before hitting the floor? (HINT: round to the nearest whole number)

300 joules

The number of seconds in one week:

31,557,600

Jasmine, who weighs 400 newtons moves up a 5.0-meter climbing wall in 15 seconds. The amount of power generated by Jasmine as she climbs the wall is about _____ watts. (HINT: FIND WORK FIRST, THEN POWER.)

345

How many centimeters is 15 inches?

38.1 cm

A machine uses an input force of 200 newtons to produce an output force of 800 newtons. What is the mechanical advantage?

4

Forces in a diagram are represented by the following scale: 1 centimeter equals 5 newtons. To represent a force of 20 newtons, the length of an arrow drawn to represent the force should be ____ centimeter(s).

4

A 0.2 kg baseball is pitched with a velocity of 40 m/sec and then batted to the pitcher with a velocity of 60 m/sec. What is the change of momentum of the ball?

4 kg x m/sec

A boy whose mass is 40 kilograms runs at 5 meters per second and jumps onto a 10-kilogram stationary sled. The boy slides on the sled over a horizontal, frictionless surface at a speed of: (HINT: conservation of momentum formula)

4 m/sec

A ball is moving at 6.0 m/s and has a momentum of 24.0 kg·m/s. What is the ball's mass?

4.0 kg

There are __________ Newtons in 1 pound.

4.448

The momentum of a 2000 kilogram car traveling at 20 meters per second is:

40,000 kg·m/sec.

A ball is dropped off the roof of a tall building. If the ball reaches the ground in 3 seconds, how tall is the building? (HINT: find the distance)

44.1 meters

Determine the resultant Force on the object below: (See physics photo album) #3.4

9 N to the left

What is the one missing force on the following object that should be in equilibrium? (See physics album) #1.2

4N; left

Jade pulls on a wagon with 3 newtons of force toward east. Laura pulls on the same wagon with 4 newtons of force toward north. The magnitude of the wagon's resultant force is ____ newton(s). (Hint: calculate the "c".)

5

Running up a flight of stairs, Maria gnerates 450 watts of power. If it takes her 6 seconds to go up the stairs, the amount of work she does in running up t

506

If I drop a watermelon from the top of one of the dorms at South Alabama, and it takes 3.34 seconds to hit the ground, calculate how tall the building is in meters.

54.66m

Gina wheels her wheelchair up a ramp using a force of 80 newtons. If the ramp has a mechanical advantage of 7, what is the output force?

560 N

A ramp with a MA of 6 is used to move a 36 N load. What input force is needed to push up the ramp

6 N

Determine the resultant Force on the object below: (See physics photo album) #1.4

6 N to the left

Frank starts from a certain point and moves east towards Henry's house for 7 miles, then goes north for 5 miles, and then turns west for 3 miles. Using the graph below what is the magnitude ("c") of the resultant vector for Frank? (Hint: use the Pythagorean theorem) ( See physics photo album)

6.40 mi

A 5 meter ramp lifts objects to a height of 0.75 meters. What is the mechanical advantage of the ramp

6.67

Which of the following is NOT in scientific notation? Select one: a. 1.1987 x 103 b. 612.56 x 104 c. 4.56 x 1018 d. 8.642 x 10−3

612.56 x 104

A skydiver reaches an instantaneous velocity of 88.2 meters per second before opening his parachute. How long was he in free fall? (HINT: find the time from velocity)

9 seconds

What is the one missing force on the following object that should be in equilibrium? (See physics album) #3.2

6N; left

If a 40,000 kilogram rocket were traveling from its launch pad at a speed of 150 meters per second, 800 kilograms of gases would be expelled from the rocket at a speed of about: (HINT: after collision formula)

7,500 m/sec

Convert this number to scientific notation: 0.0000780

7.80 x 10 ^-5

You are walking in Paris alongside the Eiffel Tower and suddenly a croissant smacks you on the head and knocks you to the ground. From your handy dandy tourist guidebook you find that the height of the Eiffel Tower is 300.5 meters. If you neglect air resistance, calculate how many seconds the croissant dropped before it tagged you on the head.

7.83 sec

If Antonia exerts a force of 700 N to walk 6 m up a flight of stairs in 6 s how much power does she use

700 W

Use Newton's second law of motion to calculate the mass of an object when a force of 34 N accelerates the object 4 m/sec2

8.5kg

Solve for the net force of the the free body diagram below. (See physics album) #3

9N; right

All of the following are considered to be simple machines EXCEPT: a. scissors b. a bike c. a jackknife d. a seesaw

A bike

An unpowered mechanical device, such as a lever, that works by a single movement is known as horsepower.

False

To increase the final momentum of a racquetball, the player should: a. swing the racquet as fast as possible. b. follow through when hitting the ball. c. increase contact time with the ball. d. All of the above

All of the above

The diagram below represents a cart traveling from left to right along a frictionless surface with an initial speed of 3 m/sec. At what point is the potential energy least? (See physics photo album)

B

The relationship between a spring's change in length and the force it exerts is called:

Hooke's Law

Which of the following is an example of Newton's third law of motion? Select one: a. hitting a baseball with a bat b. sitting in a chair c. Both A and B d. none of the above

Both A and B

A variable that remains unchanged throughout an experiment is called the:

Control variable

The equation that correctly expresses Newton's second law is:

Force = mass x acceleration

The newton is defined as the:

Force that can give a 1-kilogram mass an acceleration of 1 m/s2

The fixed point around which levers rotate is called the

Fulcrum

fixed point on a lever about which the lever rotates is called the:

Fulcrum

According to the conservation of momentum, the momentum before a collision should be ____________ momentum after a collision.

Greater than the

Alex helps his teacher lift a 200-N box of books 1.2 m from the floor to the desktop. In which of the following situations will he do more work?

He lifts a box 1.7 m from the floor

A student is planning an experiment to find out how the height from which he drops a balls affects how high the ball bounces. The dependent variable is the:

Height the ball bounces

The change in an object's momentum is equal to

Impulse

If an object is speeding up, then one knows for certain that the momentum of the object is _________.

Increasing

The force, work, energy, or power applied to a machine is called the:

Input

The side of a lever between the fulcrum and the input force is called the

Input arm

In a theoretical machine, work:

Is always less than the work input

Liz throws a softball with a force of 63 N a distance of 25 m. Jamie throws the softball with the same amount of force but the ball only goes 17 m. Which girl does less work

Jamie

Work may be measured using units of:

Joules

What is the proper SI unit for mass?

Kilogram

Please classify the following as a type of potential energy or kinetic energy. A bicysclist pedaling up hill.

Kinetic energy

Please classify the following as a type of potential energy or kinetic energy. A bowling ball rolling down the alley.

Kinetic energy

A screwdriver can be used to open a c an of paint. In this situation the screwdriver is being used as a

Lever

What is the proper SI unit for volume?

Liter

A mechanical system capable of performing work

Machine

A word meaning "size"often used to describe scalar quantities and includes units of measurements is:

Magnitude

A scalar is a quantity that can be completely described by a single value using:

Magnitude only

The ratio of the output force to the input force is called the

Mechanical advantage

Which of the lists show units arranged in order from smallest to largest?

Millimeter, centimeter, meter, kilometer

Which of the following statements about the conservation of momentum is NOT correct?

Momentum is not conserved for a system of objects in a head-on collision.

The metric unit of force preferred by scientists is the:

Newton

The metric unit for work is the:

Newtons per second

What is happening to the object at point A? (See physics photo album for picture)

Positive acceleration

Please classify the following as a type of potential energy or kinetic energy. A cowboy and his horse are standing on a cliff watching the sunset.

Potential energy

Please classify the following as a type of potential energy or kinetic energy. An archer with his bow drawn.

Potential energy

A student wants to conduct an experiment to find out how pulse rate changes as the length of time spent exercising increases. The dependent variable will be:

Pulse rate

Which of the following formulas can we use to calculate the magnitude of a vector given components? a. Newton's Formula b. Hooke's Formula c. Pythagorean Theorem d. Vectors Formula

Pythagorean theorem

A simple machine, such as a pulley, will sometimes multiply you

Several times

Vector quantities include all of the following EXCEPT: a. velocity. b. force. c. speed. d. acceleration.

Speed

The force directed along the ropes of a rope and pulls system is called

Tension

force that stretches or pulls:

Tension

A ball with a mass of 1 kilogram is moving in a straight line at the same speed as a ball with a mass of 10 kilograms. What must be true of the force required to stop the balls?

The forces required to stop the balls cannot be determined from the information given.

The force, work, energy, or power produced by a machine is known as the output.

True

The rate at which work is done and measured in Watts is known as power.

True

A child's toy is suspended from the ceiling by means of a string. The Earth pulls downward on the toy with its weight force of 8.0 N. If this is the "action force," what is the "reaction force"?

The toy pulling upward on the Earth with an 8.0-N force.

The side of a lever between the fulcrum and the output force is know as the output arm.

True

A unit of power and is equal to 746 Watts is known as as the horsepower.

True

Which of the following objects has the greatest amount of momentum?

Turtle

Which of the following situations is an example of a mostly elastic collision?

Two billiard balls collide and bounce off each other.

A measured quantity that is described by stating a magntude (size) and a direction is called a:

Vector

A wheelbarrow is an example of a(an):

Wheel and axle

Which of the following is not considered a simple machine? a. Wedge b. Pulley c. Lever d. Wheelbarrow

Wheelbarrow

Of the following, the largest unit of speed is: Select one: a. meters per second. b. kilometers per hour. c. miles per hour. d. inches per second.

a. Meters pers second

Newton's first law is also known as the law of:

inertia

All of the following may be the result of an inelastic collision EXCEPT: a. permanent change in the shape of the colliding bodies. b. kinetic energy released as sound. c. colliding bodies stick to one another. d. zero loss of kinetic energy.

Zero loss of kinetic energy

An impulse is equivalent to

a force multiplied to time

Which of the following is an example of a dependent variable? Select one: a. how much a plant grows in different amounts of light b. the different monkeys you use to see which one can jump the highest c. the different states (OH, KY, IN) when comparing who has the most snow days d. the different trees you measure to see which one is the tallest (sugar, maple, pine, or elm)

a. how much a plant grows in different amounts of light

The rate of change in the speed of an object is known as:

acceleration

The slope of a speed versus time graph represents:

acceleration

Jonah is pushing his younger sister, Jessica, on a swing. If Jessica weighs 350 kilograms, how much higher above the ground must Jonah push her to increase her potential energy by 5250 joules? (HINT: use potential energy formula and solve for height!)

action and reaction forces are applied to different objects.

If three balls of different materials were dropped at the same time from the same height, which would hit the ground first? (Assume there is no air resistance.)

all at the same time

Action-reaction forces

always act on different objects

Units of measurement used to label a quantity of acceleration are:

cm/sec^2

When two objects hit each other, a(n) ____ occurs.

collision

The set of perpendicular vectors that add up to a given vector

components

If the net force acting on a moving object is zero, the object will:

continue in the same direction with no change of speed.

When a force applied to an object causes the object to move in the direction of the force, the object requires:

energy

When the net force acting on an object is zero, this ALWAYS causes a condition of no motion referred to as:

equilibrium

According to Newton's third law of motion, when a hammer strikes and exerts force on a nail, the nail

exerts an equal force back on the hammer

A carefully designed test done under controlled conditions is called a(n):

experiment

A structured procedure for collecting information to test a hypothesis is a(n)______.

experiment

Inertia is used when explaining Newton's

first law of motion.

In science, work is defined as:

force multiplied by the distance moved in the same direction as the force.

When an object is accelerating due to the force of gravity with no other forces acting on it, it is:

free fall

The force that one surface exerts on another when the two rub against each other is called

friction

The force that resists the motion of objects or surfaces in contact with one another is called ____.

friction

The acceleration of gravity is defined as

g= 9.8 m/sec2

What is happening to the object at point B? (See physics photo album for picture)

has a constant speed

An object that has momentum MUST be

moving

The action that would require no work to be done is:

holding a 100-pound object over your head

As the force acting on an object increases, the acceleration of the object

increases

Kinetic energy increases as a marble:

increases speed down an incline.

As the speed of a rolling ball is increasing, the increasing speed is accompanied by:

increasing momentum

An inclined plane reduces the effort force by

increasing the distance through which the force is applied

A machine is classified as a compound machine if it

is made up of two or more parts

The skateboard on which you are standing moves as one of your feet pushes on the ground because the force you apply on the ground:

is pushing back

If an object is accelerated, all of the following may occur EXCEPT:

it remains motionless

The power of a machine measures

its rate of doing work

Which of the following is the largest unit? Select one: a. decimeter b. meter c. kilometer d. millimeter

kilometer

A series of forces was applied to each of two blocks, A and B. The graphs below show the relationship between the force and the acceleration for each block. Compared to the mass of block A, the mass of block B is: (See physics album)

larger

With unbalanced forces, the object will move in the direction of the _________ force.

larger

The mechanical advantage of a lever is the ratio of the

length of input arm/length of output arm

The inertia of an object is related to its:

mass only

What is the proper SI unit for length?

meter

Because it is based on factors of 10 and is easy to work with, scientists prefer to use the ____ system.

metric

Which of the following is the smallest unit? Select one: a. milligram b. microgram c. kilogram d. decigram

milligram

The impulse applied to an object is equal to the change in the object's:

momentum

Acceleration of an object must be caused by a force that is:

not zero

In an experiment studying how increasing amounts of acid rain affect the number of organisms in a pond, which of the following would be the dependent variable?

number of organisms in pond water

Energy that is stored due to the position of an object may be called ____ energy.

potential

The independent variable on a graph can be described as the variable:

represented on the x-axis. never changes in the experimental system. over which a scientist has direct control when designing the experiment.

The simple machine that operates as a ramp that curves around a shaft is a:

screw

The unit of time used most commonly by physicists and other scientists is the:

second

Static friction is greater than _______ for almost all combinations of surfaces.

sliding friction

The slope of a position versus time graph represents:

speed

What is the dependent variable in the pictured graph? (See physics photo album for picture)

speed

A constant that represents the relationship between the force exerted by a spring and its change in length

spring constant

A force acting on an object does no work if

the force is not in the direction of the object's motion

Terminal speed occurs when:

the force of gravity is balanced by the air resistance of an object.

When a spring is compressed:

the potential energy stored in the spring increases.

A rocket can fly into space because:

the rocket pushes on exhaust gases and the exhaust gases push back on the rocket

The inertia of two objects must be the same if:

the same force causes the same acceleration in both objects

Two swimmers relax close together on air mattresses in a pool. One swimmer's mass is 48 kg, and the other's mass is 55 kg. If the swimmers push away from each other,

their momentum is equal but opposite.

"Forces occur in pairs" is another way of stating Newton's:

third law of motion

On his way to a concert, John stops at the mall to buy some camera film. If you divide the distance he travels to the concert by his average speed for the entire trip, you are calculating:

time interval

The ability to cause change is defined as:

work/energy and is measured in joules

If a force vector acting in a east-west direction is resolved into its x-components (x axis; horizontal direction), any vector acting in the north-south direction would be called a(n):

y-component