Force

Question 1

what is force?

Answer 1

force is a push or pull movement

Question 2

what does force cause?

Answer 2

accelerations

Question 3

A force caused by gravity

Answer 3

W- weight

Question 4

A force in a rope or cable

Answer 4

T- tension

Question 5

A force caused by a object in contact with another surface

Answer 5

N- normal force

Question 6

A force that opposes motion of an object

Answer 6

F-friction

Question 7

3 steps to solving elevator problems

Answer 7

1. sketch free body diagram
2. write down given and unknowns
3. EFy -> up-down = ma or 0

Question 8

when will up-down = ma

Answer 8

when there is an acceleration

Question 9

when will up-down= 0

Answer 9

when there is a constant speed

Question 10

what is g’s value

Answer 10

positive 9.8

Question 11

if an elevator is going up and speeding up then…

Answer 11

Vf>Vi because it got faster and thge acceleration is positive

Question 12

if an elevator is going up and slowing down then…

Answer 12

Vf<Vi because it is slowing down and acceleration is negative

Question 13

if an elevator is going down and speeding up then…

Answer 13

Vf>Vi because they are both negative and the acceleration is negative

Question 14

if an elevator is going down and slowing down then…

Answer 14

Vf<Vi but they are both negative and the acceleration is positive

Question 15

If there is constant speed there must be?

Answer 15

friction

Question 16

horizontal, Fx=?

Answer 16

right-left= ma

Question 17

vertical, Fy=?

Answer 17

up- down= ma

Question 18

terminal velocity

Answer 18

the maximum speed an object can go in free fall

Question 19

with atwood machine problems the differences in mass cause?

Answer 19

acceleration

Question 20

newtons third law

Answer 20

for every action there is an equal yet opposite reaction

Question 21

example of an action-reaction force pair

Answer 21

ball hits bat, bat hits ball with equal force
man runs into wall, wall pushes against man with equal force

Question 22

unbalanced forces cause…

Answer 22

acceleration

Question 23

newtons first law

Answer 23

an object at rest will remain at rest and an object in motion will remain in motion with constant velocity unless acted on by a net external force

Question 24

inertia

Answer 24

tendency of object to resist any change in its motion

Question 25

how is inertia measured?

Answer 25

by mass in Kg

Question 26

newtons second law

Answer 26

acceleration of an object is directly proportional to the net force acting on it and inversely to its mass

Question 27

equation for newtons second law

Answer 27

Fg=ma

Question 28

forces cause…

Answer 28

accelerations

Question 29

accelerations change…

Answer 29

velocities

Question 30

friction

Answer 30

a force caused by interaction of body with its surroundings
-opposes the motion of an object

Question 31

if Fs=F

Answer 31

the object will not move

Question 32

if Ff=Ft

Answer 32

object will move at a constant speed

Question 33

Fs=?

Answer 33

static (stationary) force of friction

Question 34

Fk=?

Answer 34

kinetic (moving) force of friction

Question 35

object moves if…

Answer 35

F is greater than Fs

Question 36

kinetic friction is always ____ than static friction

Answer 36

less

Question 37

Ff(s) equation

Answer 37

u x Fn

Question 38

Ff(k) equation

Answer 38

u x Fn

Question 39

as a ramp becomes steeper static friction must…

Answer 39

increase

Question 40

constant speed means what?

Answer 40

equilibrium