Net Force
A boy pulls a wagon with a force of 6 N east as another boy pushes it with a force of 4 N east. What is the net force?
10 N east
What is the formula for calculating speed?
Speed = Distance / Time
When a car suddenly stops, the objects in the back seat are thrown forward. This is explained by which of Newton's laws?
Newton's First Law- the law of inertia
An airplane flying at a constant speed
Balanced
What is a balanced force?
Forces on an object that do not change the motion of the object
---------> [ ] -------->
30 N 30 N
Which of the following statements accurately describe the forces?
Select TWO correct answers.
F. The two forces would be added to determine the net force.
G. The two forces would be subtracted to determine the net force.
H. The net force would be 60 newtons to the right.
J. The net force would be 60 newtons to the left.
K. The net force would be 0 newtons to the right.
F and H
The two forces would be added to determine the net force.
The net force would be 60 newtons to the right.
Michael is riding a 4 kg bike and pushes on the pedals with a net force of 80 N. What is the approximate acceleration of the bike?
Acceleration = Force / Mass
20 m/s2
Mr. Robbins is taking his baby for a walk in a stroller. The amount of force that Mr. Robbins must use to make the stroller move MOST likely depends on the stroller's...
A. Distance
B. Mass
C. Velocity
B. mass
A car accelerating, braking, or turning?
Unbalanced
What is an unbalanced force?
Forces on an object that cause change in the motion of the object
Dr. Johnson and his wife were trying to move their new chair. Dr. Johnson pulls with a force of 30 N while Mrs. Johnson pushes with a force of 25 N in the same direction. What is the net force?
55 N in the same direction
What formula is used to find the acceleration of an object?
Acceleration is solved by taking the force exerted on the object and dividing it by the mass of the object.
A = F/M
Vincent and Xavier are pushing a 40 kg box with a force of 55N. The box slowly slides across the room as they push. What is the acceleration of the box as it slides across the floor?
Round to the hundredths place (0.00)
Acceleration = Force / Mass
1.38 m/s2
A moving train that slows down as it approaches the station.
Unbalanced
What is speed?
The rate of change of position (or distance traveled) with respect to time
The classes are playing tug of war. Ms. Key's homeroom pulls with a force of 50 N on the left. Mr. Fabro’s homeroom pulls with a force of 45 N in the opposite direction. What is the net force? Who won?
5N to the left, Ms. Key's class won
A diagonal line on a speed vs time graph moving downward on the y-axis demonstrates a car...
slowing down, speeding up, or moving at a constant speed
slowing down
A student throws a ball to a friend. What causes a ball to fall downward?
gravitational force (gravity)
Which examples are balanced forces and which are unbalanced?
A. a parked car
B. pushing against a wall
C. riding a skateboard downhill
Balanced: A and B
Unbalanced: C
The sum of all the forces acting on an object
You and your brother are pushing a car with a dead battery with forces of 20 N and 25 N in the same direction. What is the net force applied on the car?
45 N
How are speed and velocity different?
Velocity includes SPEED and DIRECTION
A high school baseball team in Dallas travels south to Austin to participate in a tournament. The trip from Dallas to Austin is about 322 kilometers. The trip requires about 3.5 hours to complete on a school bus. Which of the following best represents the VELOCITY of the bus?
92 km/h South
Which examples are balanced and which are unbalanced forces?
A. a football entering a 3-point goal at increasing speed
B. ice floating still in water
C. driving to school and taking a left into the parking lot
D. sitting in a chair
Balanced: B and D
Unbalanced: A and C
What is acceleration?
A change in motion caused by an unbalanced force acting on an object; includes increasing speed, decreasing speed, or a change in direction