Newtons Laws 1
Which law explains Inertia?
Newtons First law
What force is always effecting objects on Earth?
Gravity
Which shopping cart will accelerate faster-a small one with a mass of 5kg or a large one with a mass of 3kg?
A large one with a mass of 3 kg
Which law talks about action and reaction?
Newton's 3rd Law
What unit do scientists use to measure acceleration?
m/s2
If you increase the force applied to an object, does the acceleration increase or decrease?
Acceleration increases
A box is being pushed to the right across the floor. What force is acting towards the left?
Friction
What unit do scientists use to measure force?
Newtons
Example of a non-contact force?
answers may vary
What is an example of a contact force?
answers may vary
What is interia?
The tendency of an object to continue its motion unless an outside force acts on it
A bowling ball collides with a set of bowling pins (at rest) with a force of 15N. What is the force the pins exert on the bowling ball.
15N
A car and a train are going the same speed. Which one is easier to stop? Why?
The car because it has less mass
What unit do scientists use to measure mass?
kg or grams
Describe an objects motion when it has balanced forces.
Not moving/moving at a constant speed
A parachuter has a mass of 55kg and falling at an acceleration of 9.8m/s2. How much force is being exerted on the parachuter by gravity?
f = ma = 55kg*9.8m/s2 = 539N
A car with a mass of 1,500kg is accelerating at 20m/s2. How much force is exerted on the car by the engine?
f = ma = 1,500kg*20m/s2 = 30,000N
A baseball has a mass of 3kg. The baseball player hits it with his bat and it accelerates at a rate of 10m/s2. How much force is exerted on the ball by the bat?
f = ma = 3kg*10m/s2 = 30N
You push a box with a mass 22kg across the floor at an acceleration of 7m/s2. How much force is being exerted on the box by you?
F = ma = 22kg*7m/s2 = 154N
You open a door with a mass of 6kg. The door opens at an acceleration of 2m/s2. How much force is being exerted on the door by you?
f = ma = 6kg*2m/s2 = 12N
Summarize Newton's 1st Law
An object does not change motion unless an outside force acts upon it
Summarize Newton's 2nd Law
The larger the mass of an object the larger the force needed to change its motion.
A baseball player hits a ball. The action force is the force of the ball on the bat. What is the reaction force?
The force of the bat on the ball.
Summarize Newton's 3rd Law
For every action there is an equal and opposite reaction
A puppy that has a mass of 8kg is pulling you across the yard. You have a mass of 15kg. You are accelerating at a rate of 4m/s2 across the yard. How much force is being exerted on you by the puppy?
f = ma = 15kg*4m/s2 = 60N