Name Date Per

Force ÿ Newton's Laws Assignment 2014

Forces - Label each arrow with push, pull, friction, or 9rarity. Identify if the force is balanced orunbalanced and which direction it wi[[ move.

415N

iON

I. Balanced?

15N

3. Balanced?

2. Balanced? Direction?

Direction?

30N 8N

i2N

15N

Direction?

4. Balanced? Direction?

5. Balanced? Direction?

50N

150N

6. Balanced? Direction?

7. As the skydiver fails, the friction (airresistance) becomes equal to the downwardpuff of gravity. When these two forcesbecome equal in magnitude, what wi[[happen to the skydiver?

Circle the best answer.

/ ' i,ÿ, ,,,

t000 Newtons"ÿ-..ÿ :ÿ ................................................................................................................. iI

1000 Newtÿs J

1. The forces shown above are PUSHING / PULLING forces.2. The forces shown above are WORKING TOGETHER/OPPOSITE.3. The forces are EQUAL/NOT EQUAL.4. The forces DO / DO NOT balance each other.5. The resuttant force is 1000 N TO THE RIGHT / 1000 N TO THE LEFT /

ZERO.6. There IS /IS NO motion.

j'l..,,,,.,,ÿ,*'ÿ" 200 Newtons

7. The forces shown above are PUSHING / PULLING forces.8. The forces shown above are WORKING TOGETHER/OPPOSITE.9. The forces are EQUAL/NOT EQUAL.10. The forces DO ! DO NOT balance each other.11. The stronger force is putting to the RIGHT / LEFT.12. The weaker force is putting to the RIGHT / LEFT.13. Motion is to the RIGHT / LEFT.

Newton's 2nd Law Problems- use the formula in your notes

I • How much force is needed to accelerate a68 kilogram skier at 1.2 mls2?

6. What is the mass of an object that needs aforce of 4,500 N to accelerate it at a rate of5 m/s2?

2. What is the acceleration of a 2,000-kg truckif a force of 4,200 N is used to make it startmoving forward?

7. What is the acceleration of a 6.4-kg bowlingbat[ if a force of 12 N is applied to it?

3. What is the acceleration of a 0.30 kilogrambait that is hit with a force of 25 N?

4. What is the mass of an object that requiresa force of 30 N to accelerate at 5 m/s2?

5. What is the force on a 1,000-kiLogramelevator that is fatting freely under theacceleration of gravity only (9.8 m/s2)?

8. CaLcuLate the acceleration of a 40-kg crateof voLLeybaLL gear when puLLed sidewayswith a net force of 200N.

9. CaLcuLate the acceleration of a 2000-kgsingLe-engine airplane as it begins totakeoff with an engine thrust of 500N.

Boxes are shown below with various masses on a friction-free table. Arrows are not to scale.

A, B.

............ " ....... :ÿ ' "ÿ-'ÿ'ÿ'ÿ":ÿÿÿ"ÿ' l

C. D,

ION 20 kR15N

10. Find the net force on each. Rank them in order from greatest to [east. Rank"

A B C D

11. Find the accelerations of the boxes. Rank them from greatest to Least. Rank"A: B" C" D"

Laws of Motion

WHICH LAW?We're told that Sir Isaac Newton discovered some things about motionwhen an apple dropped on his head. Whatever "force" was behind hisdiscoveries, we have benefited from his discoveries.Here are his three laws of motion. You should be familiar with them.Fil! in the missing words in each of the three laws. Then tell whichlaw fits each example below.

?

T

Which law? First, Second, or Third?

1. A frog leaping upward off his lily pad is pulled downward by gravity and lands onanother lily pad instead of continuing on in a straight line.

2. As the fuel in a rocket ignites, the force of the gas

back of the rocket and pushes theexpansion and explosion pushes out the

rocket forward.

3. When you are standing up in a subwaytrain, and the train suddenly stops, yourbody continues to go forward.

4. After you start up your motorbike, as yougive it more gas, it goes faster.

5. A pitched baseball goes faster than onethat is gently thrown.

6. A swimmer pushes water back with herarms, but her body moves forward.

7. As an ice skater pushes harder with hisleg muscles, he begins to move faster.

8. When Bobby, age 5, and his dad areskipping pebbles on the pond, thepebbles that Bobby's dad throws gofarther and faster than his.

object at stays at-- ata

or an object that is ÿ----keepsin a straight

unless anothermoving at that

acts on it.

NEWTON,s SECOND taw OF MOTION:

The amount of-ÿ needed tomake an object change its

depends on the ÿ-ÿ-

and the --ÿ-ÿ--ÿ of the object

--- required.

9. When you paddle a canoe, the canoe goes forward.

10. A little girl who has been pulling asled behind her in the snow is cryingbecause when she stopped to tie herhat on, the sled kept moving and hither in the back of her legs.

NEWTON'S THIRD LAW OF NOTION:(,or force), there is an

For everyaction (or force).

and

Name

Basic Skills/Physical Science 6-8+28 Copyright ©1997 by Incentive Publications, Inc., Nashville, TN.