In what way (directly or inversely) is the kinetic energy of an object proportional to its velocity, and by what factor (linear, squared, cubed)?
Kinetic energy is proportional to velocity squared.
100
When is Newton's second law rendered invalid?
At speeds close to that of light.
100
If the initial kinetic energy of an object is 10J and its final kinetic energy is 25J, what is change in kinetic energy (∆K)?
15J.
100
How many postulates of special relativity did Einstein create?
Two.
200
What is the proportionality of the change in kinetic energy from one inertial frame of reference to any other?
Direct (1:1). OR They are always the same.
200
What is true about the laws of physics for an observer in any inertial frame of reference?
They are the same.
200
If an observer is travelling at 4.0m/s [L], what is the magnitude and direction of a stationary object from their point of view?
4.0m/s [R]
200
Whose law did Einstein disprove at speeds of close to light?
Newton's Second Law.
300
Is there a proportionality of kinetic energies at different inertial frames of reference?
No, it is only the change in kinetic energy that remains constant (and therefore proportional) at different inertial frames of reference.
300
If you are running with your phone and drop it how will the phone appear to fall:
a) to you?
b) to a stationary bystander?
a) Straight down.
b) Parabolically.
300
If the change in kinetic energy on a mass of 2.0kg is 20J and the initial kinetic energy of said mass is 5.0J, what is its final velocity?
Note: ∆E = Ef - Ei
+/-5.0m/s.
300
What does Einstein have in common with the duck in the physics textbook?
Their first name (Albert).
400
Given the formula on the board for relativistic mass, is relativistic mass directly or inversely proportionate to the velocity of the object?
Directly proportionate.
400
Why is the mass of an object only considered to change at speeds close to that of light? (Hint: use the formula for relativistic mass)
Because in cases of lower speed the speed of the object is insignificant compared to that of light.
400
If the velocity of a given mass is 2.6x10^8m/s, what is the ratio of the relativistic mass to the rest mass?
2:1.
400
How old was Einstein in 1905 if this year (2014) was the 59th anniversary of his death at the age of 76?