Classical Mechanics
Express the unit newton (N) in terms of base SI units
kg m s-2
What is the term for the point at which a substance changes from a gas to a liquid at a constant temperature and pressure?
Condensation
According to Ohm's Law, what is the relationship between current (I), voltage (V), and resistance (R) in an electrical circuit?
V = IR
What is refraction?
the phenomenon in which light bends as it passes from one medium to another due to a change in its speed
(T/F) Electromagnetic force is 1036 times stronger than gravitational force
True
According to Newton's first law of motion, what is the natural tendency of an object regarding its motion?
Inertia
What is the difference between heat and temperature?
Heat is a measure of total kinetic energy
Temperature is a measure of the average random kinetic energy.
(T/F) An ideal voltmeter has an infinite resistance
True
What type of electromagnetic waves have the second longest wavelength in the electromagnetic spectrum?
Microwaves
Why does metal feel cold?
Heat from your hand is rapidly conducted away from your skin
When are SUVAT/kinematic equations used?
When acceleration is constant
What is absolute zero? Express it in terms of degrees Celcius.
The lowest possible temperature
-273.15 °C
What is the term for a circuit component that stores electrical energy and releases it when needed?
Capacitor
What optical phenomenon is responsible for the vibrant and shifting colors seen on the surface of soap bubbles?
Thin film interference
Why is the sky blue?
Blue light is scattered more than the other colors because it travels as shorter, smaller waves.
What is the formula for Young’s modulus (E), and what is it a measure of?
a measure of the stiffness or elasticity of a material
E = (Stress) / (Strain)
where stress = F/A and strain = ΔL/L
What does the second law of thermodynamics state about entropy?
the total entropy of an isolated system can never decrease over time and tends to increase until it reaches a maximum
Why does the resistance of LDR (Light-dependent resistor) decrease as light intensity increases?
The light energy produces more free electrons which increases the current for a certain voltage across the LDR
Write the formula for the Doppler effect for a moving observer
f' = f ((v± u)/v) where v = velocity of waves and u = velocity of observer
Why is it colder at higher altitudes despite being closer to the Sun?
There are fewer air molecules; when the pressure of a gas decreases, the temperature also decreases
OR Adiabatic cooling
What is an equation for the total spring constant of two springs in series with spring constant k1 and k2, respectively?
k = (1/k1+1/k2)-1
What is Maxwell's demon?
A hypothetical, intelligent being that can sort fast-moving (hot) gas molecules from slow-moving (cold) ones within a container. It violates the 2nd law by decreasing entropy
What is the formula that relates the input voltage (Vin), output voltage (Vout), primary turns (NP), and secondary turns (NS) in a transformer?
Vin/Vout = NP/NS
According to Hubble's law, what is directly proportional to their distance from Earth?
The redshift of light from distant galaxies
What is the name transformation that aligns the space and time coordinates of two systems moving relative to one another at a constant velocity?
Lorentz transformation