Dynamics Flashcards
What quantities does a vector have?
A vector has both magnitude (size) and direction.
What is the Law of Conservation of energy?
Energy cannot be created or destroyed
What is the calculation for acceleration?
a= v-u/ t
What is Newton’s 2nd law of motion?
an unbalanced force will cause an acceleration, F=ma
What does mass mean?
Mass – measure of the quantity of matter in an object (kg)
What is a projectile?
A projectile is an object in motion under the influence of gravity.
How do you measure average speed?
Measure distance, d, between light gates using metre stick
Measure time, t, for vehicle to travel between light gates (mask passing through light gates trigger the timer to start then stop)
Average speed, v(bar) is calculated by using v(bar)=d/t
Gravity causes an acceleration at what speed?
9.8ms/2
What does weight mean?
Weight – force due to gravity acting on mass (N)
What is the formula for the vertical velocity?
Vv= g t
What two components does a projectile have to their motion?
Horizontal- constant speed due to balanced forces
Vertical-downwards acceleration (9.8ms/2) due to gravity.
What is the unit for power?
Watts
State an example of Active energy.
Kinetic, heat, light. electrical
State an example of Active energy.
Kinetic, heat, light. electrical, sound
State an example of Potential energy
gravitational, chemical, nuclear, strain
Is energy a scalar or vector quantity?
Scalar- it has only size(magnitude)
Which of Newton’s laws of motion does F=ma relate to?
Newton’s second law of motion
What does a downward slope on a velocity-time graph indicate?
A negative acceleration
What is instantaneous speed?
Instantaneous speed is the speed of an object at a point in it’s journey
What is displacement a measure of?
Displacement is the length of a straight line between two points in a specific direction.
How do you calculate the distance from a graph?
d= area under the graph
What happens when an object freefalls through the air?
In freefall, objects accelerate due to gravity,
g = 9.8 ms-2). This is due to the unbalanced force of their weight, (W=mg
What happens when an object reaches it’s terminal velocity?
The increasing air resistance will equal the weight, giving a balanced force, so that no acceleration occurs.
This is the highest speed the object can fall =terminal velocity.
What is gravitational potential energy?
A field in which a mass experiences a force
What is Kinetic energy?
A moving object that has both mass and velocity
What is a satellite?
A satellite is an object in orbit around a larger object
What type of path does a satellite have?
A circular path
What is the calculation for work done?
Ew= F d
What is the formula for power?
P= E/t
What is the formula for kinetic energy?
Ek=1/2 m v2
What is a satellite?
A satellite is a object that moves round a larger object
Example: the moon orbiting the Earth
How do you calculate instantaneous speed, using an experiment?
Measure mask size, d, using ruler
Measure time, t, for mask to travel through light gate (timer starts when beam of light gate is broken by mask, then stops when mask moves out of beam)
instantaneous speed, v, is calculated using v=d/t
What can potential energy change into during motion?
An object falling from a height will lose Ep and gain Ek as it falls. As energy is conserved, Ep lost = Ek gained
How do you calculate the resultant force when the forces are unbalanced?
Find the difference of the forces
Is velocity a vector or a scalar?
A vector
