Motion Study Guide

  1. What does it mean for an object to be in motion?

WHEN AN OBJECT’S DISTANCE FROM ANOTHER OBJECT CHANGES. WHEN IT MOVES FROM A REFRERNCE POINT

  1. What is velocity? Give an example of a velocity.

THE SPEED AN OBJECT IS TRAVELING AND THE DIRECTION IT IS TRAVELING. EX: 75 MPH NORTH

  1. What are possible SI units of measurements for speed?

METER/SECOND (CAN BE KM/HOUR)

  1. What is the basic SI unit for length?

METER (M)

  1. Is there a relationship between speed, distance, and time? If so, what is it?

YES THE SPEED IS FOUND BY DIVIDING DISTANCE BY TIME; S=D/t

  1. If you are showing the speed of an object on a line graph, what should you label the X and Y axis?

Y-AXIS: DISTANCEX-AXIS: TIME

  1. What is the slope of a line? What does it tell you? How do you calculate it?

THE STEEPNESS OF THE LINE, THE ANGLE THAT IS CREATED BETWEEN IT AND THE X-AXIS

  1. What does a horizontal slope tell you?

NO ACCELERATION; OBJECT MOVING AT A CONSTANT SPEED

  1. What two things can change to cause acceleration to occur?

SPEED & DIRECTION

  1. What type of line shows acceleration?

DIAGONAL

  1. What is acceleration? What is deceleration? Give an example of each.

ACCELERATION: INCREASE IN SPEED EXAMPLE: RUNNER BEGINNING A RACE

DECELERATION: DECREASE IN SPEED EXAMPLE: RUNNER ENDING A RACE

  1. What is the formula used to calculate acceleration?

a=SF – Si/T OR a=f/m

  1. What is inertia? What law is sometimes called the “law of Inertia”?

OBJECT’S RESISTANCE TO CHANGE MOTION; NEWTON’S 1ST LAW

  1. Briefly Explain Newton’s 1st, 2nd, & 3rd Laws of Motion.

1ST: OBJECTS WILL CONTINUE TO DO WHATEVER THEY ARE DOING UNTIL AN UNBALANCED FORCE CHANGES IT

2ND: THE AMOUNT OF ACCELERATION IS AFFECTED BY THE MASS AND FORCE THAT IS APPLIED; IF YOU INCREASE THE MASS THE ACCELERATION WILL DECREASE; IF YOU INCREASE THE FORCE THE ACCELERATION WILL INCREASE

3RD: FOR EVERY ACTION THERE IS AN EQUAL & OPPOSITE REACTION

  1. Which of Newton’s laws explains the relationship between force, mass and acceleration? What is the relationship?

2ND: THE AMOUNT OF ACCELERATION IS AFFECTED BY THE MASS AND FORCE THAT IS APPLIED; IF YOU INCREASE THE MASS THE ACCELERATION WILL DECREASE; IF YOU INCREASE THE FORCE THE ACCELERATION WILL INCREASE

  1. How do you calculate acceleration and force according to Newton’s 2nd law?

a=f/m

  1. What is the action-reaction principle?

APPLYING A FROCE TO ONE OBJECT CAUSES THAT OBJECT TO APPLY A FORCE BACK

  1. What is momentum? What are the basic units of momentum?

HOW HARD IT IS TO STOP AN OBJECT THAT IS IN MOTION kg *m/s

  1. Explain the law of conservation of Momentum?

MOMENTUM IS NOT LOST WHEN TWO OBJECTS COME IN CONTACT WITH EACH OTHER; IT IS COMBINED

  1. A 300-N force acts on a 25-kg object. The acceleration of the object is ____.

a=F/M

=300N/25KG

=12kgm/s2

  1. A 3,000-N force acts on a 200-kg object. The acceleration of the object is ____.

a=F/M

=3000N/200KG

= 15Nkg

  1. What are the different types of friction? Explain each one.

ROLLING: HAPPENS BETWEEN A ROUND AND FLAT OBJECT

STATIC: KEEPS AN OBJECT FROM MOVING

SLIDING: KEEPS TWO SOLID OBJECTS FROM SLIDING ON EACH OTHER

FLUID: CREATED WHEN AN OBJECT MOVES THROUGH A LIQUID OR GAS

  1. What happens when balanced forces act on an object? What happens when they are unbalanced?

BALANCED: NOTHING, THE OBJECTS REMAINS STATIONARY

UNBALANCED: THE OBJECT MOVES IN THE DIRECTION THAT THE STRONGER FORCE IS MOVING IN

  1. Draw a picture of balanced forces acting on an object.

50N 50N

  1. Draw a picture of unbalanced forces acting on an object.

50N100N

What do the following units represent? Use D for distance, T for time, S for speed, or A for acceleration.

D 1. 14 kmT 4. 6 hours D_ 7. 14 mi D 10. 1.4 m

S 2. 30 m/sS 5. 12 cm/s2T8. 3.2 sec A 11. 6 cm/sec/sec

T 3. 34 min S 6. 150 mph D9. 25 ft A 12. 3 km/hr/sec

  1. At exactly 2:00 pm, Speedy the Snail crawls onto a meter stick at the 10 cm mark. If he reaches the 65 cm mark at exactly 2:10 pm, what is his speed?

S = D/T

=55 cm/10min

=5.5 cm/min

  1. A car travels 300 km in six hours. What is the speed of the car?

S = D/T

= 300 km/ 6 hrs

= 50 km/hr

  1. A golf ball travels at 16 m/s, while a baseball moves at 7 m/s. The mass of the golf ball is 0.045 kg and the mass of the baseball is 0.14 kg. Which has the greater momentum?

GOLF BALL: p = mv

= (.045 kg)(16m/s)

= .72 (kg)(m)/s

BASEBALL: = (.14 kg)(7 m/s)

= .98 (kg)(m)/s

BASEBALL HAS MORE MOMEMENTUM

  1. A steel ball whose mass is 2.0 kg is rolling at a rate of 2.8 m/s. What is its momentum?

p = mv

= (2.0 kg)(2.8 m/s)

= 5.6 kg*m/s

  1. A race car leaves the starting line and travels 36000 m in the first 600 seconds of the race. They are then forced to take a pit stop and don’t go anywhere for 250 seconds. After the pit stop, they finish the race, going 24500 m in 350 seconds.
  2. What is the car’s average speed during the first part of the race (before the pit stop)?

S=D/t

= 36000m / 600 s

= 60 m/s

  1. What is the car’s average speed during the pit stop?

S=D/t

= 0 m/ 250 s

= 0 m/s

  1. What is the car’s average speed after the pit stop?

S=D/t

= 24500m / 350 s

= 70 m/s

  1. What is the car’s average speed for the whole trip?

S=Total Distance/ total time

= (36000m + 0m + 24500m) / (600s + 250s + 350s)

= 60500m / 1200 s

= 50.42 m/s

Time (s) RUN / Distance (m)RISE
0 / 0
1 / 2
2 / 8
3 / 18
4 / 32
5 / 50
  1. Graph the data.
  2. What does this graph represent?

The slope of the line

  1. What is the slope of the line in this graph (show your work)?

Slope = Rise/Run

=

  1. Brittney pushes Haley who sitting on a swing. Haley has a mass of 500 kg and accelerates at arate of 40 m/s2. Find the force exerted by Brittney.

F = ma

= (500 kg)(40 m/s2)

= 20,000 N