What is a force?
What is a PUSH or PULL on an object.
Which is NOT an example of a balanced force?
a. A Stanley cup sitting on a table
b. A football flying in the air at a constant speed
c. A basketball being dribbled down the court
A basketball being dribbled down the court
Which object would require the most force to move?
a tennis ball
a baby
a car
a cell phone
car, because it has the most mass
Which situation best describes overcoming the force of gravity?
A. Sitting in a chair.
B. Jumping up and down.
C. Standing next to your friends.
D. Eating lunch.
B. Jumping up and down.
How do you calculate speed?
Speed = distance / time
If these boys are each pulling with the force of 10 newtons. What will happen?
The boy in blue will win.
They will not move at all.
The boy in red will win.
They will not move at all. Balanced
You push a friend sitting on a swing. She has a mass of 50 kg and accelerates at a rate of 4 m/s2. What is the force?
200 N
A football gets punted and travels 90 meters in 9 seconds, what is the football’s speed?
10 m/s
What is acceleration?
The change in an objects velocity.
Which of the following statements is true?
Balanced forces cause a change in velocity.
Unbalanced forces cause a change in velocity.
Forces do not affect the change in velocity.
Unbalanced forces cause a change in velocity.
A car is going at a 30mph for 3 hours. The driver is headed North to visit family for the holidays.
This is an example of...
a. acceleration
b. velocity
c. speed
velocity, he has a constant speed and a direction.
A bicyclist is going at a constant speed in a figure 8 pattern. Is this speed, velocity, or acceleration?
Acceleration
(acceleration is any change in speed and/or direction)
What is friction?
The force that acts directly against the direction of motion.
You want to move two boxes. One is 30 kg and the other is 45 kg. Which box would require more force to move it?
a. More force is needed to move the 30kg box.
b. More force is needed to move the 45kg box.
More force is needed to move the box with more mass.
A heavy box sits on the floor with the force of 3 N pushing left and the force of 5 N pushing right. Gravity is pulling the box down to the floor with 2 N and the force of the floor is pushing the box up with 2 N. Which statement best identifies the result of all forces acting on the box?
A. The box doesn't move at all.
B. The box moves left.
C. The box moves right.
D. The box moves downward.
C. The box moves right with 2N
The air blowing up on an air hockey table causes the puck to...?
A. Air balances the forces and makes the puck move faster.
B. Air causes the puck to slow down.
C. Air causes the puck to have less mass and travel farther.
D. Air reduces friction and allows the puck to move easily.
D. Air reduces friction and allows the puck to move easily.
What does Newton's 3rd Law state?
That every action has and equal and opposite reaction.
An object that is moving at a constant speed, with no change in motion, is considered a ___________ force.
Balanced
What will happen if they push against each other with equal force when they both have the same mass?
They will both move backwards the same distance
You are pulling a wagon that is 50 kg and you are going at a constant rate (m/s) with a force of 100 N. If the wagon mass doubles to 100 kg and you want it to go at the SAME constant rate as before, how much force would be needed to pull the wagon?
200N
Get acceleration first which is 2 m/s
Then take 100kg (new mass) and multiply by original acceleration of m/s.
What is inertia?
The tendency of an object to continue doing what it is doing.
What is the net force?
A woman is pushing a shopping cart with a force of 40 N. The frictional force of the ground is 6N. What is the net force?
34 N forward
Which of Newton's laws demonstrates why seatbelts in cars are important? And why do you think it is this Law?
Newton's 1st law, becasue without seatbelts Inertia would take over passengers.
Give an example for all 3 Laws of Motion and be able to explain which Law it goes with.
Student answers will vary.