Newton`s Second Law

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Newton’s Second Law
Newton’s second law of motion explains how
The total force on an object is equal to its
This is shown as:
If you are looking for acceleration, the equation is:
What does our circle equation look like?
Newton’s Second Law
Newton’s second law of motion explains how
Force, Mass, and Acceleration are related.
The total force on an object is equal to its
acceleration and its mass multiplied together.
This is shown as:
F=mxa
If you are looking for acceleration, the equation is:
a=F/m
What does our circle equation look like?
F
m
a
Sample Problems
1.)A 52kg water-skier is being pulled by a speedboat. The
force causes her to accelerate at 2 m/s/s.
Calculate the net force that cause this acceleration.
2) What is the mass of an elevator, which has a 2000N force
applied to it to accelerate it at 2m/s/s?
Sample Problems
3.)Suppose you know the acceleration of a shopping cart
as it rolls down the aisle. You want to find the total (or
net) force with which it was pushed. What other
information do you need in order to find the force?
4) Suppose you double the force acting on an object. In
what way could you change the mass to keep its
acceleration unchanged?
Sample Problems
5) What is the acceleration of a 55 kg cart
being pushed with a force of 825N?
Sample Problems
1.)A 52kg water-skier is being pulled by a speedboat. The
force causes her to accelerate at 2 m/s/s.
Calculate the net force that cause this acceleration.
Force = Mass x Acceleration
F = 52 kg x 2 m/s/s
F = 104 kg-m/s/s
F = 104 N
2) What is the mass of an elevator, which has a 2000N force
applied to it to accelerate it at 2m/s/s?
m=F/a
m = 2000N / 2 m/s/s
m = 1000 kg
Sample Problems
3.)Suppose you know the acceleration of a shopping cart
as it rolls down the aisle. You want to find the total
(or net) force with which it was pushed. What other
information do you need in order to find the force?
Mass of the shopping cart
4) Suppose you double the force acting on an object. In
what way could you change the mass to keep its
acceleration unchanged?
If the total force is doubled, you have to double
the mass of the object to keep the acceleration
unchanged.
Sample Problems
5) What is the acceleration of a 55 kg cart
being pushed with a force of 825N?
F=mxa
a=F/m
a = 825N / 55 kg
a = 15 m/s/s
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