Motion
This is the metric unit for speed
This is the metric unit for KE
What is meters per seconds?
What is a joule?
This is the equation for speed.
What is DISTANCE/TIME?
To determine ______________ you calculate the change in speed per unit of time.
What is ACCELERATION?
The definition for force.
What is PUSH OR PULL?
The tendency of an object to resist a change in motion.
What is INERTIA?
An object is in motion if it changes position relative to this.
What is a REFERENCE POINT?
This is speed with direction.
What is VELOCITY?
This is why the moon is still considered to be accelerating, even if it moves at a constant speed around the Earth.
What is CHANGING DIRECTION?
The sum or difference of all forces acting on an object.
What is NET FORCE?
How can the gravitational force between two objects decrease?
Increase mass
Decrease distance
The formula for acceleration is
V final - V initial/ time
Can the acceleration of a car change even when its speed remains constant?
Yes, the car can change direction.
The three ways you can accelerate.
What is INCREASING SPEED, DECREASING SPEED, and CHANGING DIRECTION?
*Show picture
What are the values for D and E if there is a net force of 60N to the left?
E = 300N
D = 20N
Explain at least 2 reasons Venus and Mercury have no moons
Distance from the sun - compete with Sun's mass and gravitational pull
Mass of the planets - they have a relatively small mass therefore small gravitational pull.
In the 2008 Beijing Olympics, Eamon Sullivan of Australia swam 100 m in 47 seconds to win the gold medal and set a record. Calculate his average speed and include proper SI units.
s = d / t
s = 100 m / 47 s
s = 2.1 m/s
Sound travels at a rate of 330.0 m/s. How long does it take for the sound of thunder to travel 1500m?
Show Formula
Plugged in values
Answer with units
The amount of inertia an object has depends on its _____.
Mass
State all 3 of Newton's Laws of Motion
Law of Inertia - an object at rest will stay at rest until acted on by an unbalanced force
Law of Force - an objects acceleration is dependent on its mass and the force applied to it
Every action force has an equal and opposite reaction force
What is the Kinetic Energy of a 1200 kg object that is moving with a speed of 24 m/s?
Show Formula
Plugged in values
Answer with units
KE=(m x 0.5) x (v2)
(1200 x 0.5) x (242)
KE = 345,600 J
A parked car speeds up to 110.0 m/h in 25.00 seconds. What is the acceleration?
Show Formula
Plugged in values
Answer with units
V final - V initial/ T
110-0/25
4.4 m/s2
Which of the following is NOT an example of unbalanced forces acting on an object?
A. An acorn falling from a tree, accelerating
B. A car changing speed from 50 km/h to 80 km/h
C. A car moving straight at 80 km/h
D. A truck slowing down as it approaches a stop sign
C. A car moving straight at 80 km/h
Cindy is very excited. She has been asked to ride on a float in a parade! During the parade, she stands in the middle of the float and waves to the crowd while the float is in motion at a constant speed. While she is waving, she sees her friend standing in the crowd. Cindy jumps straight up as high as she can so that her friend will see her.
When Cindy lands back on the float, where will she land? Assume no air resistance.
Using one (or more) of Newton’s laws of motion, explain why the girl moved the way she did.
She will land in the same place on the float where she jumped
This is related to Newton’s first law (1)
Cindy will continue her forward motion even though she is no longer in contact with the float due to inertia
An object of mass 30 kg is falling in air and experiences a force due to air resistance of 50 newtons. *(Remember gravity on Earth has an acceleration of 9.8m/s2)
A. Determine the net force acting on the object
f=ma
f=30 x 9.8
f=294N
Net force is 294-50 = 244N
Classify the following as a type of potential energy or kinetic energy (use the letters K or P)
1. A bicyclist pedaling up a hill _____
2. An archer with his bow drawn _____
3. A volleyball player spiking a ball _____
4. A baseball thrown to second base _____
5. The chemical bonds in sugar _____
6. The wind blowing through your hair _____
7. Walking down the street _____
8. Sitting in the top of a tree _____
9. A bowling ball rolling down the alley _____
10. A bowling ball sitting on the rack _____
1. K
2. P
3. K
4. K
5. P
6. K