Click here to this assignment (x)

Download Report

Transcript Click here to this assignment (x)

Name ___________________________________________ Date _______________ Period ___________
PHYSICS PRACTICE PACKET
THIS PRACTICE PACKET IS DUE ON ___________________ the ___________ of _____________.
This packet will give you the practice necessary to master the skillz that you’ll need to succeed in this
unit. It will be due on the day listed above, which is the day of the unit quiz. You may work on it by
yourself or with a group, as long as you understand what you write down and you are an active participant in
your own learning. You may work at your own pace, but the entire thing must be finished, without exception
on the date listed above.
PART I – VOCABULARY
Directions: Use a dictionary or the interwebs to define the words below. If there are multiple definitions,
make sure that you pick the one that makes the most sense given how we use the word in our class.
1. Force:
2. Work:
3. Power:
4. Vector:
5. Scalar:
6. Acceleration:
7. Cosine:
8. Tangent:
9. Pressure:
10. Gravity:
PART II – CALCULATION PRACTICE
A. NEWTON’S SECOND LAW
1. A 10 kg box is sitting on the floor on Earth. What is the force that the box is putting on the ground?
2. A rather large 7 kg cat is sitting on a table on Earth. What is the force that the cat is putting on the table?
3. Your friend throws a 0.25 kg baseball at your face with a force of 400 N. What is its acceleration?
4. Jerome makes a 10 kg ice sculpture of a squirrel, but it slips off the table and falls to the ground on Earth.
Amazingly, it breaks into two, perfectly-even pieces. What is the force that each piece puts on the ground?
5. Henry pushes a cart that has a mass of 100 kg with a force of 10 N. What is the acceleration of the cart?
6. Henry’s twin Harvey pushes a cart with a mass of 100 kg with a force of 10,000 N. What is the
acceleration of the cart?
7. Justin Bieber is sitting at her table having tea with her dolls on Earth. The teapot has a mass of 1 kg.
How much force is it putting on the cute little tea table?
8. Patrice makes a cake while on a trip to an unknown planet. The cake has a mass of 2 kg and is resting on
a table with a force of 100 N. What is the acceleration due to gravity on this planet?
9. A paperclip with a mass of 0.002 kg is accidently left on the floor on Earth. A table with four legs and
with a mass of 50 kg is placed on the paperclip so that the paperclip is under only one of the legs. What is
the force that is pushing down on the paperclip?
10. Duane is on a spaceship and wants to land on an unknown planet. His computer tells him that the crust
of the planet is very thin, and can only support a force of 22,000 N. Duane’s spaceship has a mass of 4,000
kg and his sensors indicate that the acceleration due to gravity is exactly half that of Earth. Can Duane
safely land?
B. NEWTON’S FIRST AND THIRD LAWS
1. Sally pushes on a wall with a force of 500 N. With what force does the wall push on her?
2. Two cosmonauts, Fyodo and Dimitri, are floating in the middle of their spaceship. They push against
each other. What happens?
3. A ball is rolling along a rough road at a speed of 5 m/s. After 25 seconds, what will have happened to the
ball?
4. Nigel and Whitney are both pushing on opposite sides of a large walrus. If they push with equal force but
in opposite directions, what happens to the walrus?
5. Nigel and Whitney now push on the same side of the walrus. What happens? How do you think the
walrus feel about this?
C. NEWTON’S LAW OF UNIVERSAL GRAVITATION
1. What is the force of attraction between a 10 kg ball and a 70 kg human that are standing 1 m apart?
2. What is the force of attraction between the sun and a planet with a mass of 5.4 x 1060 kg that is 6.5 x 1020
m away?
3. What is the force of attraction between a smartphone with a mass of 0.15 kg sitting on a table 1.5 m away
from a person with a mass of 60 kg?
D. WORK AND POWER
1. If a woodchuck uses 30 W of power to chuck 10 g of wood, how much wood could a woodchuck chuck
by using 9,000 W of power?
2. If a cat that weighs 400 N runs up a flight of stairs that is 15 m tall, how much work has the cat done?
3. How much work do you do on a crate full of kittens if you push on it with a force of 540 N and move it a
distance of 12 m?
4. How much power can a hydroelectric turbine produce if it does 50,000 J of work in 3 seconds?
5. If a 60 kg human on earth walks up a ramp that is 20 m tall, how much power has she used?
6. Janette, whose mass is 54 kg, finds a tree stump on earth that is 0.4 m tall. She jumps up on it in 0.79
seconds. How much power has she used?
7. How much work does a snowplow do if it pushes a pile of snow with a weight of 7,600 N a distance of 2
m?
8. If Edmund has 5 kg of toast on earth, how much work does it take to move his huge pile of toast 15 m?
9. Julian takes 5 minutes to do 6,700 J of work. How much power has he developed?
10. How much power does it take to pick up a 300 N puppy from the floor in 4 seconds and put it in your
lap if your lap is 0.6 m above the floor?
E. HEAT
1. How much energy does it take to boil (that is, to bring it to 100 °C) 11 L of water if it starts at 23°C?
2. What mass of water can you heat from 45 °C to 65 °C with 9,000 J of energy?
3. How hot can you get 5 L of water if it starts at 22 °C and you add 2,400 J of energy to it?
4. How much energy does it take to heat 400 g of water from 3 °C to 40 °C?
5. What is the specific heat of 600 g of a substance that takes 5,600 J of energy to heat it from 40 °C to 70
°C ?
F. PROJECTILE MOTION
1. Justin Bieber is tossed off a 700 m cliff on earth. Neglecting air resistance, how long does it take him to
hit the ground?
2. A car going 20 m/s rolls off a cliff that is 200 m tall. How long does it take to hit the ground?
3. If a 4,000 kg piano is dropped off a building and falls 50 m into a crowd, how long do the people
underneath have to scramble out of the way before it hits the ground?
4. A car going 25 m/s rolls off a cliff that is 800 m above the ground. How far away from the cliff does the
car land?
5. A bullet is fired out of a gun held by a 1.8 m person on earth with an initial velocity of 1,000 m/s. How
far away from the gun will the bullet hit the ground?
6. A bullet with a mass of 0.005 kg is fired straight up into the air on earth. The initial velocity of the bullet
is 400 m/s. How long does the person firing the gun have to get out of the way before the bullet hits the
ground?
7. What is the acceleration due to gravity on a planet if a piano dropped from a spaceship flying 7,000 m
above the surface of the planet takes 500 seconds to hit the ground?
8. If you drop a 1,000 kg piano off a 400 m cliff on the moon, where the acceleration due to gravity is 1.62
m/s/s, for how many seconds will it have to fall before it hits the ground?
9. If the same piano from question number 8 was dropped from the same cliff, but on Earth, how much
faster would it hit the ground?
10. Carlos is 1.5 m tall. He fires a bullet out of a gun on Earth with an initial velocity of 900 m/s. The
target for which he is aiming is 2,000 m away. Will the bullet make it to the target before it hits the ground?
G. BRING IT ALL TOGETHER
1. How much force does it take to accelerate a car from 10 m/s to 15 m/s?
2. With what force would a car traveling at 25 m/s hit a wall if it took 0.001 seconds to stop fully?
3. You and your friend are having a game of tug-of-war. You are pulling with a force of 500 N while your
friend is pulling with a force of 900 N. Your mass is 70 kg, and that of your friend is 60 kg. Who wins the
game and what is their acceleration?
4. A person with a mass of 70 kg is holding a gun. A bullet with a mass of 0.01 kg is shot out of the gun
with an acceleration of 500 m/s/s. What is the acceleration that the person holding the gun experiences?
5. Ferdinand wants to lift a 4 kg picnic basket up to his tree house using a pulley. The tree house is 20 m
above the ground. He ties the basket to one end of a rope, loops it around the pulley and pulls on the other
end from the ground. How much power does it take to lift the basket if it takes him 1 minute to get the
basket up to his tree house?
6. If you have a pot filled with 14 L of water at 20 °C, and you put it on a stove that puts out 4,000 J of
energy every minute, how long will it take to boil the water (that is, get it to 100 °C)?
7. Justin Bieber is fired out of a human cannonball thingie at a circus, and the cannon is aimed parallel to
the ground. The cannon is mounted 20 m above the ground, and the Biebs is fired with an initial velocity of
60 m/s. You would prefer to have him hit the ground, but the circus insurance people require you to have a
1.5 m thick foam mat on which he can land. How far away from the cannon should you put the mat so that
he doesn’t break his face?
8. A daredevil gets into a barrel and goes over Niagara falls, which is 51 m tall. How long should it take the
barrel to hit the ground?
9. A large, 8 kg cat is sitting on a table. You sneak up behind it, make a noise like an angry emu and scare
it. The cat jumps 1 m into the air and returns back to the table, stopping in 0.001 seconds. What is the force
of the cat when it hits the table?
10. A 10,000 kg bus runs into a wall at 20 m/s and takes 0.002 seconds to stop. With what force does the
wall push back on the buss, assuming that the wall doesn’t move?