F=ma Calculations
A 5 kg object accelerates at 2 m/s2 when a force is applied to it. What is the force?
10 N
The scientific term that describes an object's tendency to resist change in motion.
inertia
When a hammer hits a nail with a force of 70 N, what force does the nail hit the hammer with?
70 N
What happens when the net force acting on an object is zero?
The object will not accelerate
Which law would we use to understand how mass affects force?
2nd Law
When a 200 kg object is hit with a force of 50 N, what is the resulting acceleration?
0.25 m/s2
The scientific term for when the forces acting on an object do not all cancel each other out
unbalanced force
When Mr. Chu hits a whiffle ball with a bat, why doesn't the force of the bat hitting the ball and the force of the ball hitting the bat cancel each other out?
Because the ball and the bat/Mr. Chu are separate systems with different masses.
Scientific term for a push or pull
force
What causes a change in motion?
An unbalanced force
If an object accelerates at 55 m/s2 when struck with a force of 11 N, what is its mass?
0.2 m/s2
The object accelerates
Complete the sentence:
For every action force there is...
...an equal and opposite reaction force
What are the units used in a calculation for Newton's second law?
Kilograms, Newton's, meters per second squared
The force that opposes motion?
friction
In a frictionless environment, Ms. Chelukhova tries to push a refrigerator with a mass of 120 kg. How much force must she apply to accelerate the fridge 0.15 m/s2?
18 N
Daily Double
This is the scientific/mathematical term used to describe the relationship between acceleration and mass, given an equal force.
While walking, a person is propelled forward by what force?
The reaction force of the ground pushing the feet/leg/person
What are the action/reaction forces when someone uses a canoe?
Paddle pushes the water backward, water pushes the paddle forward.
How many kilograms are in 2500 grams
2.5 kg
Ruben is trying out a new RC car on different surfaces. The car has a mass of 2 kg and is capable of applying 2 N of force to the ground through each of its tires.
If the car is only accelerating at 2 m/s2, what is the force of friction on the surface he is testing?
The car SHOULD accelerate at 4 m/s2, but is only accelerating at 2 m/s2, so friction is decelerating the car at 2 m/s2.
The force required to decelerate a 2 kg object at 2 m/s2 is 4 N.
Describe what would happen to the path of the Earth if the Sun were to instantaneously disappear
The Earth would stop its elliptical orbit and travel through space in a straight line, only deviating due to the gravity of other objects it interacts with.
Why would a car using a strong magnet on the end of a pole NOT accelerate?
The car, pole, and magnet are all part of the same system, and forces within the same system cancel eachother out.
Daily Double
On the International Space Station, an astronaut suspends his camera in the middle of the compartment. As the space station burns it's rocket, the camera appears to move towards the back of the compartment. Explain.
Describe how a parachute works using Newton's laws
The parachute creates friction with the air in which the falling parachute initiates a downward force and the air applies an equal and opposite force. This is called "air resistance"