Motion and forces Flashcards
(22 cards)
Define velocity
Velocity is the rate of change of displacement
What is Newton’s 3rd Law of Motion
Newton’s 3rd Law of Motion states that the force exerted by one body on a second body is equal in magnitude and opposite in direction to the force simultaneously exerted by the second on first body
Define distance
Distance is the total length moved by an object regardless of its direction of motion
How to find displacement from a vt graph
Area under graph
Define Newton’s 2nd Law of Motion
Newton’s 2nd Law of Motion states that the rate of change of momentum of a body is directly proportional to the external net force acting on the body and is in the same direction as external net force
Define Newton’s 1st Law of Motion
Newton’s 1st Law of Motion states that a body at rest will remain at rest, and a body in motion will continue to move at constant velocity, unless acted on by a net external force
Mathematical representation of N2L
dp/dt proportional to F(net)
Why does a rocket have a delay before takeoff
- Thrust needs to exceed weight for rocket to accelerate and takeoff
- Initial thrust is lower than weight
- Delay allows for thrust to exceed weight
Formula for acceleration
a = dv/dt
Define linear momentum
Linear momentum of a body is the product of its mass and velocity
What are the scalar SUVAT equations
v = u + at
s = ut + 0.5at^2
v^2 = u^2 + 2as
s = (u + v) / 2 x t
What conditions must be met for an action-reaction pair of forces
- Act on different bodies
- Equal in magnitude
- Opposite in direction
- Same type
How to find acceleration from a vt graph
Gradient
Define acceleration
Acceleration is the rate of change of velocity
Define speed
Speed is the rate of change of distance
Define displacement
Displacement is the linear distance from a fixed position in a specific direction
Equation for weight
W = mg
When is an object in a state of free fall
When the only force acting on it is its weight
Formula for velocity
v = ds/dt
What property of a body resists change in motion
Mass
Equation for Hooke’s Law
F = kx
Define inertia
Inertia is the natural tendency of a body to obey N1L
