††††††††††††††††††††††† ††††††††††† Chapter 12 Math Practice
Speed ††††††††††† = distance/time†††† ††††††††††† ††††††††††† 365 days = 1 year
+ direction†††††††††† ††††††††††† 0.62 miles = 1 km
change in velocity/time†††† †††††††††††
x velocity††††††††† †††††††††††††††††††††††
Distance ††††††††††† =
Ĺ X acceleration x time2††††† ††††††††††† 100 cm = 1m
Acceleration Due to Gravity = 9.8 m/sec2 or 32
ft/ sec2†††††††† ††††††††††††††††††††††† †††††††††††
weight = Force = mass x acceleration††††† ††††††††††† ††††††††††† N/kg = m/sec/sec††††††††
Universal Law of Gravitation† Forcegravity = Gravitational constant(mass1mass2)/radius2
Gravitational constant = 6.67 x 10-11 N-m2/kg2
kg-m/sec/sec †= N††††††††††††††††† ††††††††††††††††††††††† ††††††††††† velocity
of sound† = 1100 ft/sec
On a separate sheet of paper
FOR EACH PROBLEM DO THE FOLLOWING ALWAYS!!!!!
the formula that you intend to use to solve the problem. †††††††††† 1 pt.
everything you did to get to the answer.††††††††† †††††††††† †††††
†††††††††† 2 pts.
your final answer.††††††††† †††††††††† †††††††††† †††††††††† †††††††††† †††††††††† 1 pt.
jogger runs the first 1000m of a race in 250 sec.† What is the joggerís speed?
2.† A student practicing for a track meet ran 250 m in 30 sec.† What was her average velocity?
- †A Space Shuttle travels in orbit at
21,000 km/hr.† How far will the
Space Shuttle travel after 5 hours?
- A car
traveled 1025 km from El Paso to Dallas in 13.5 hours.† What was its average velocity?
fast was a plane flying if it traveled 400 km in 30 min?
- If the
average speed of a car is 45 km/hr, how far can the car travel in 40 min?
speed of light is 3 x 108 m/sec.† How long does it take light to travel
†††††† 149 x 109 m distance from the sun to the earth?
- If the
speedometer of your car reads 30 mph, how far will you go in 15 min?
table below shows Jackís travels on his skateboard.
††††††††††† ††††††††††† A.†
What was Jackís speed from T5 to T 10 seconds?
††††††††††† ††††††††††† B.†
What was Jackís average speed for the entire ride?
- A car
accelerates from 0 to 72km/hr in 8 sec.†
What is the carís acceleration?
space ship is traveling at 20,000 m/sec.†
At T=5 sec, the rocket thrusters are turned on.† At T =55 sec, the space ship reaches a
speed of 24,000 m/sec.† What is the
space shipís acceleration?
driver starts his parked car and within 5 sec reaches a velocity of 54
km/hr as he travels east.† What is
car-traveling north with a velocity of 30 m/sec slows down to a velocity
of 10 m/sec within 10 sec.† What is
the cars deceleration?
sprinter accelerates out of the starting blocks to a speed of 10 m/sec in
one sec.† What is the sprinters
- If a
car completes a 3-mile oval track in 58 seconds, what is the average
speed?† Explain whether or not the
car accelerated during this 58 seconds.
your car goes from 0 to 60 miles per hour in 6 seconds, what is the
objects travel at an average acceleration of 9.8 m/sec/sec.† If an object falls from a tall
building, how long will it take before it reaches a speed of 49 m/sec?
penny is dropped from the top of the Sears Tower in Chicago.† Acceleration due to gravity is 32
ft/sec2.† It takes 9.5
seconds to fall.† What is the
velocity of the penny just before hitting the ground?
student drops a rock down a mineshaft.†
It takes 3 seconds for the rock to hit the bottom of the shaft,
what is the velocity of the rock just before impact?† The acceleration due to gravity is 9.8
hare and the tortoise are at the starting line together.† When the gun goes off, the hare moves
off at a constant speed of 10 meters per second.† The tortoise starts more slowly, but accelerates at the rate
of 1 meter per second per second.†
Make a table showing the positions of the two racers after 1
second, 2 second, 3 seconds, and so forth until the tortoise passes the
stone is dropped from a bridge and hits the water 2.5 s later.† What is the final velocity of the
stone?† What is the height of the
parachutist jumps from a plane and starts to freefall at 1500 ft.† His parachute fails to deploy.† Make a table and a graph of his
velocity and distance every 250 ft.
- A rock
falls to the bottom of a tall canyon, falling freely with no air
resistance, for 4.5 seconds.† Make
a table of the distance traveled by the rock and its velocity after 1.0 s,
2.0 s, 3.0 s, 3.5 s and 4.5 s.
steel ball whose mass is 100 g is rolling at a rate of 2.8 m/sec.† What is its momentum?
marble is rolling at a velocity of 100 cm/sec with a momentum of
10,000g-cm/sec.† What is its mass?
object whose mass is 3 kg is fired from a cannon, giving it forward
momentum of 1050kg-m/sec.† What is
- † What is the momentum of a 200-g rifle
bullet traveling at 300 m/sec?
is the momentum of a 1000 kg truck†
that is traveling at 0.1 m/sec?
- A race
walker can walk 1 mile in 10 minutes.†
What is the speed in miles per hour?† In km per hour?†
long will it take the above race walker to walk 3 miles?† 10 km?
far can the above race walker walk in 45 minutes?† In 1.5 hours?
North American Plate is moving away from the European plate at a constant
speed of 4.2 cm per year?†
the average distance between the two plates is 7000 km, and the two
plates have maintained their constant speeds, how long ago were the two
typical motorist in the United States travels 25,000 miles in his or her
car every year.† If you assume that
the average speed of the car while traveling is 45 miles per hour,
calculate the total number of hours an average motorist spends in his or
her car.† How many hours per day?
typical airborne speed of an intercontinental 747 jet is 530 miles per
hour, while the airborne speed of the supersonic Concorde is 1500 miles
per hour.† If each airliner were to
circumnavigate the earth (25,000miles) what would be the difference in air
time between the two aircraft?
takes light 8.33 minutes to travel from the sun to earth, and 1.3 seconds
from earth to the moon.† What is
the average distance of the sun and moon from earth?† The speed of light is 3 x 108
- †While traveling out in the country at 50
miles per hour, your carís engine and brakes stop working and you coast to
a stop in 25 seconds.† What was
your average deceleration during the time after the motor stopped working
until you stopped?
from rest, a train will reach a final, constant speed in 35 seconds while
accelerating at a constant speed of 3 km/hr/sec.† What is the final speed of the train?†
- 50 N
of force is applied to move a round rock that has a mass of 5.0 kg.† What will be the acceleration of the
rock when the force is applied?
- A 2.5
kg bowling ball accelerated at a rate of 50 m/sec2.† What was the force that was applied to
the bowling ball?
is the force on a 10 kg ball that is freefalling due to the pull of
- A man
has a mass of 66 kg on earth.† What
is his weight?
- A girl
on roller skates accelerates at a rate of 2 m/sec/sec with a force of 100
N.† What is her mass?
person weighs 540 N on the earth.†
What is the personís mass?
- On the
moon the acceleration due to gravity is 1.67 N/kg.† What is the weight of a person on the
moon with a mass of 60 kg?
is the gravitational attraction between an 80 kg man and a 50 kg woman who
are 2 m apart?
is the distance between two 3200 kg elephants when they are apart and
exerting a gravitational force of 3.8 x 104 N?
acceleration due to gravity on the surface of Mars is 0.4 m/s2.† How much would a man weigh on the
surface of Mars if his weight on earth is 180 N?
has a mass of 1.9 x 10 27 kg.†
The sun has a mass of 2 x 1030 kg.† The distance between Jupiter and the
sun is 7.8 x 108 km.†
What is the gravitational force between the sun and Jupiter?
has a mass of 6.0 x 1024 kg.†
The distance from the sun to the earth is 1.5 x 1011 m.
The gravitational force between the sun and earth is 3.6 x 1022
N.† What is the mass of the sun?
is it easier for a person to swim, on the earth or on the moon?† Assume that they both have liquid
the gravitational forces on two identical masses- one of them floating in
water and one lying on a table identical?†
rocket leaves earth along a radial path with a constant acceleration equal
to the acceleration due to gravity at the earthís surface.† How does the weight of a passenger
change with distance from the earth?
the air density in a spacecraft change when it enters the state of
weightlessness?† Explain why.
does an object weigh less at the equator than at the poles?
- A 90
kg man stands in an elevator cab.†
When it starts to move the scale reads 720 N.† Is the cab moving upward or
downward?† Explain.† Is its velocity constant?† What is its acceleration?
- A hole
is drilled to the center of the earth and a 1 kg stone is dropped into the
hole.† What is the mass of the
stone when it hits the bottom of the hole?† Explain.
moonís mass is approximately 1% of the earthís mass.† How does the gravitational pull of the
moon on the earth compare with the gravitational pull of the earth on the
- A 55 N
woman stands on a scale in an elevator.†
What does the scale read when the elevator is ascending at a
constant velocity of 12 m/s?† What
does the scale read when the elevator is ascending at a constant
acceleration of 3 m/s/s?† What does
the scale read when the elevator is in freefall because the cable broke?
there any circumstances when an object can be moving in a curved path and
not be accelerating?† Explain.