physics chapter 3 Flashcards
What is Rest in Physics?
A body is at rest if it does not change its position relative to a reference point over time.
What is Motion in physics?
Motion is the change in the position of a body with respect to a reference point over time.
What is Relative Motion?
Relative motion refers to the movement of one object as observed from another moving or stationary object.
Define Displacement.
Displacement is the shortest distance between the initial and final position of a body in a specified direction.
What is Velocity?
Velocity is the rate of change of displacement with time and includes direction.
What is a Frame of Reference?
A set of coordinates or a point of view used to measure and observe the position and motion of a body.
Define Acceleration.
Acceleration is the rate of change of velocity with respect to time
What does the Velocity-Time Graph represent?
It represents the change in velocity of an object over time, with velocity on the y-axis and time on the x-axis.
State Newton’s Second Law of Motion.
The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass,
F=ma.
What is Newton’s Third Law of Motion?
For every action, there is an equal and opposite reaction.
What are the Equations of Uniformly Accelerated Motion?
- Vf = vi+at
- s = vit + 1/2 at^2
- 2as = vf^2 - vi^2
where vi is initial velocity, vf is final velocity, a is acceleration, s is displacement, and t is time.
What is Newton’s First Law of Motion?
An object will remain at rest or in uniform motion in a straight line unless acted upon by a net external force.
Define Momentum.
Momentum is the product of the mass and velocity of an object, given by
p=mv.
What is Impulse?
Impulse is the change in momentum of an object when a force is applied over a time interval,
J=F×t.
State the Law of Conservation of Momentum.
The total momentum of a closed system remains constant if no external forces act on it.
What is the difference between Elastic and Inelastic Collisions?
In elastic collisions, both momentum and kinetic energy are conserved, while in inelastic collisions, only momentum is conserved, and kinetic energy is partially converted into other forms of energy.
How does Rocket Propulsion work?
Rocket propulsion works on the principle of Newton’s third law, where the expulsion of gases from the rocket generates a force that pushes the rocket forward.
What is Projectile Motion?
The projectile motion refers to the motion of an object thrown into the air, subject to only the force of gravity and air resistance, following a parabolic trajectory.
What is Instantaneous Velocity?
Instantaneous velocity is the velocity of an object at a specific moment in time.
Define Uniform Velocity.
Uniform velocity refers to motion in which an object covers equal distances in equal intervals of time, without changing direction or speed.
What is Average Velocity?
Average velocity is the total displacement divided by the total time taken,
Vavg = Δs/Δt
What is Instantaneous Acceleration?
Instantaneous acceleration is the rate of change of velocity at a specific instant.
What is Average Acceleration?
Average acceleration is the change in velocity divided by the time interval over which the change occurred,
a(avg) = Δv/Δt
What is the Slope of a Velocity-Time Graph?
The slope of a velocity-time graph gives the acceleration of the object.
