What is Force?
Friction and Gravity
Action and Reaction
Sample Problems
Current Events
100
A balanced force.
What is when two forces are exerted in different directions but with the same amount of force, resulting in no change of motion?
100
Explain friction and gravity.
Friction: the force exerted when two objects rub against one another, depends on how hard the force is and the surfaces involved. Gravity: the force which pulls objects toward each other. Measured on Earth as 9.8 m/s^2.
100
Action and reaction forces according to Newton are always...
Equal and opposite.
100
What is the weight in Newtons of a 45 kg person?
Weight= 45kg x 9.8m/s^2 Weight= 441N
100
Parents are facing neglect charges after their child fell into the cheetah exhibit at the city zoo in this american city.
What is Cleveland, Ohio?
200
Newton's first law of motion.
What is an object at rest will stay at rest, and an object in motion will stay in motion unless acted upon by an unbalanced force?
200
The three types of friction and an example of each.
What is sliding, rolling, and fluid friction. Sliding: rubbing your hands together, the Earth's plates. Rolling: the tires of a car and the pavement, rolling large blocks over logs like the ancient Egyptians. Fluid: oil in a car engine, air resistance.
200
Newton's third law of motion.
What is if one object exerts a force on another object, then the second object exerts a force of equal strength in the opposite direction.
200
What is the combined weight in Newtons held by a roller coaster with a car weight of 125 kg holding a 75 kg man and a 60 kg woman?
Weight= 125 kg+75 kg+60 kg x 9.8 m/s^2 Weight= 260 kg x 9.8 m/s^2 Weight= 2,548N
200
The U.S. Military is experimenting with making their troops an invisible camouflage using proteins from these ocean dwellers.
What is an octopus or squid?
300
An unbalanced force and the two ways a force can be unbalanced.
What is a force that can cause an object to start moving, stop moving, or change direction? Two ways: two forces exerted in the same direction will cause the object to move in that direction with the combined force of both. A larger force in one direction against a smaller force in the exact opposite direction will cause the object to move at a force of the difference of both forces in whichever direction has the stronger force.
300
Explain free fall and terminal velocity.
An object is said to be in free fall when the only force acting upon the object is gravity. Terminal velocity is when the force of gravity is equal to that of the force of air resistance.
300
The law of conservation of momentum states...
that the total amount of momentum of any group of objects remains the same unless outside forces act upon the objects.
300
What is the rate of acceleration of an object exerting 175 N of force with a mass of 35 kg?
Force=Mass x Acceleration 175 N=35 kg x Acceleration Acceleration=5 m/s^2
300
Science suggests that the transplant of this body part (not currently able to be transplanted) may soon be possible.
What is a head transplant?
400
Who is responsible for the belief that every object has a natural resting place and how did they come about this belief?
The ancient Greeks observed that a rock falling from a cliff would come to rest on the ground or that a ball would roll down a hill.
400
How does air resistance coincide with velocity and surface area?
When it comes to air resistance, objects with greater surface area will experience greater air resistance. Air resistance will continue to increase as velocity increases.
400
Remember that balanced forces have a net force of zero and they too are equal and opposite. With no force there can be no motion. How come this rule does not apply to Newton’s third law of motion?
This does not apply because Newton’s third law refers to forces on only two different objects. Forces can only be added together when they are acting on the same object.
400
One car is moving at a rate of 6 m/s with a mass of 10 kg while the next car on the track is not moving and has a mass of 30 kg. When the two cars collide the first car stops and the second car begins to move. At what velocity will the car that was not moving travel once it begins to move?
First car: Momentum=10 kg x 6 m/s Momentum= 60 kg x m/s Momentum will be transferred to second car... Second car: 60 kg x m/s= 30 kg x velocity Velocity=60 kg x m/s ÷ 30 kg Velocity=2 m/s
400
This weekend, this popular choice for the democratic representation in the 2016 presidential race officially announced that they will run for president.
Who is Hilary Clinton?
500
The theory of inertia and the first person to theorize about it.
What is the tendency of an object to resist a change in its motion? First theorized by Galileo Galilei.
500
Explain how mass and distance affects the gravitational force between two objects.
Two large objects close together will yield a large gravitational pull. Two small objects close together will yield a small gravitational pull. Two large objects far apart will yield a small gravitational pull.
500
What is momentum? What are three important things about momentum?
Momentum is the product of an objects mass and velocity. 1. Momentum always coincides with the direction of its velocity. 2. Larger the momentum the harder to the object is to stop. 3. The unit of measurement for momentum is kg x m/s.
500
Car A heads down a track towards a stationary car B at a rate of 10 m/s. When car A collides with car B the two cars join as one car. Both cars have a mass of 25 kg. Once the two cars join how fast will this new object travel?
Momentum of car A + momentum of car B M=25 kg x 10 m/s + M= 25 kg x 0 m/s Momentum of car A+B= 250 kg x m/s 250 kg x m/s= 25 kg(car A mass) + 25 kg(car B mass) x Velocity Velocity of joined car A and B= 250 kg x m/s ÷ 50 kg Velocity of joined car A and B= 5 m/s
500
Scientist shocked the world when they announced that we will see signs of extraterrestrial life in how long?
What is only 10 years?
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