Newtons Laws Flashcards
What does Newton’s First Law state about the motion of a stationary object?
If the resultant force on a stationary object is zero, the object will remain stationary.
What happens to a moving object if the resultant force acting on it is zero?
It will continue moving at the same velocity (same speed and direction).
What is required to change the velocity of an object?
A non-zero resultant force.
List the five forms of acceleration mentioned.
- Starting
- Stopping
- Speeding up
- Slowing down
- Changing direction
What is the relationship between resultant force and acceleration according to Newton’s Second Law?
The larger the resultant force acting on an object, the more the object accelerates.
How is acceleration related to the mass of an object?
Acceleration is inversely proportional to the mass of the object.
What is the formula that describes Newton’s Second Law?
F = m × a
True or False: Large decelerations can be dangerous.
True
What can large decelerations cause?
Serious injuries.
How can the force during deceleration be lowered?
By slowing the object down over a longer time.
What are crumple zones designed to do?
Increase collision times, which reduces the force.
What is the estimated deceleration of a car that comes to a stop from 15 m/s in ~1 s?
-15 m/s²
If a car has a mass of approximately 1000 kg, what is the force acting on it when it decelerates?
-15,000 N
Fill in the blank: Newton’s First Law means that an object moving at a steady speed doesn’t need a net force to keep _______.
moving
What happens to the kinetic energy of a vehicle during braking?
It transfers to the thermal energy store of the brakes.
What can happen if brakes overheat due to large decelerations?
They may not work as well and could cause the vehicle to skid.
What is the mass of the bike mentioned in the example?
10 kg
What is the mass of the man mentioned in the example?
80 kg
What acceleration is the man on the bike trying to achieve?
0.25 m/s²
