FORCES
F = ma
What is the formula for Newton's second law of motion ?
Or
What's the relationship between force, masss and acceleration ?
Projectile
What is an object moving under the influence of gravity only ?
W = Fd
What is the formula for work ?
Centripetal force
What is the name of the unbalanced force that produces circular motion ?
τ = Fd
What is the formula for torque ?
Weight
What is another term for gravitational force ?
Parabola
What is the shape of the trajectory of a projectile's path ?
E = 1/2 kx2
What is the formula for the energy stored in a spring ?
The centripetal force is at right angles to the velocity.
Why does centripetal force not increase the speed of a body ?
Equilibrium
What do you call the state where forces and torques are balanced ?
Unbalanced force
What is another term for the net, total force force acting on a body ?
There is no horizontal force.
Why does a projectile move with constant horizontal velocity ?
The total final sum of all energies is the same as the total initial sum.
The law of conservation of energy implies what about energy change ?
Tangential velocity
Describe the velocity of a body moving in circular motion
The beam does not rotate. (or rotates at constant speed).
What would be observed in a beam if the torques on it are balanced ?
Constant velocity
What motion results when balanced forces act on a body ?
The two objects land at the same time.
Compare the falling times for two objects of different mass falling from same height. OR
Compare the landing times of two objects falling the same vertical height with one moving sideways, and the other straight time.
Energy stored in a gravitational field.
What is gravitational potential energy ?
There is no longer any perpendicular force acting on the slingshot
Why does a slingshot projectile initially move off on a tangent to the circular motion when released ?
The sum of the upward vertical forces equals the sum of the downward vertical forces.
What condition must be met for a body not to accelerate upwards or downwards ?
The force is perpendicular to velocity.
What is the condition for force to act on a body without a change of speed ?
The landing speed is the same as the launch speed
Compare the initial speed of a projectile with the final; speed if it falls to the same horizontal level.
All of the of the work is used to overcome friction.
Why does the kinetic energy of a car remain constant at the same speed despite constant input of work ?
The car, turning a corner at constant speed, slides further away from the centre of the turning circle.
What happens to a car turning a corner if the centripetal force decreases ? (eg by decreased friction).
The beam would rotate clockwise, accelerating.
What would be observed in a beam if the clockwise torques on it are greater than the anticlockwise torques ?
OR What would be observed if there is an unbalanced clockwise torque on a beam ?