IB Physics
What is the meaning of equilibrium in mechanics? +
There is no net force acting on an object.
What is the condition of using suvat equations? +
The object is uniformly accelerating.
What is the meaning of work done? +
This is the process of transferring energy mechanically.
What is the internal energy of an object? +
This is the sum of kinetic energy of the particles due to random motion and the potential energy of the particles due to intermolecular forces.
What happens to the motion of the ideal gas particles at the temperature of zero kelvin? +
The particles are motionless.
What is the main difference between real cells and ideal cells? +
Real cells have internal resistance.
Why is copper the most common material in making electrical wires? +
Copper has good electrical conductivity and is low in cost.
A system is not a hundred percent efficient. What is the reason behind this? +
Because entropy tends to increase.
A room with a loudspeaker system is boomy on the bass. What is the reason behind this? +
Because the walls have reflection and standing waves are formed.
Why do people wear sunglasses on sunny days, especially when they are fishing? +
Because polaroid glasses can help to reduce light reflection from water surfaces.
Why does skidding happen when a vehicle turns around a corner at high speed on a rainy day? +
Frictional force is lacking between the tires and the road surface, there is not enough centripetal force.
How do we know the existence of certain elements on the surface of the stars? +
This can be done by observing the missing wavelength from the lights given out from the star.
Sound can be heard easily even though we can’t see the sound source. Why is that? +
Sound waves diffract easily around the corner.
Why are people now allowed to stand on the upper deck of a bus? +
Because of the rising center of gravity of the bus.
Which fundamental law in Physics is equivalent to Lenz’s law? +
Law of conservation of energy.
A charged particle is moving at constant speed in a magnetic field even though a magnetic force is constantly applied on the charged particle. Why is that? +
There is no work done from the magnetic field.
What is the direction of net force acting on a projectile moving in vacuum? + What factors will affect the amount of frictional force acting on an object moving along a rough surface? +
The type of surfaces and normal reaction.
What is the molar mass of a nuclide with mass number N? + What factor determines the speed of a traveling wave? +
The medium the wave travels through.
How can we tell whether a light wave is polarized? +
By passing the wave through the polarizer and rotating it.
A particle is moving perpendicularly into a region of magnetic field without deflection. What can be deduced about this particle? +
The particle is neutral in electric charge.
How can we correct the count rate of a radioactive source in the laboratory? +
By subtracting the background count rate from the count rate of the radioactive source
How do we know that an object performing SHM is experiencing a resistive force? +
The amplitude of the object oscillation is decreasing with time.
Which law of physics is useful in explaining the working mechanism of vehicle with propeller? + What is the meaning of inelastic collision? +
This is the collision with mechanical energy lost.
Why do we have the feeling of gaining weight when we are standing inside a lift which is accelerating upward? +
The normal reaction acting on us by the lift is greater than our actual weight.
What is the meaning of impulse? +
It is the change in momentum of an object.
How do we evaluate the internal energy of an ideal gas? +
It is the total kinetic energy of the ideal gas particles.
Why does the temperature of a substance undergoing phase change stay constant? +
The thermal energy supplied to the substance is used to break bonds.
What physics quantity of a particle will affect its orbital radius in a magnetic field? +
The mass to charge ratio of the particle.
What is conventional current? +
It is the movement of positive charge around a circuit.
What is the ideal ammeter? +
It is an ammeter with no resistance.
What is the ideal voltmeter? +
It is a voltmeter with infinite resistance.
What are fundamental or base units? +
These are the units that made up the derived units.
What are the conditions for an object to be in equilibrium? +
There are no net forces and net moments exerted on an object.
How does light travel through the optical fibers at a long distance? +
By undergoing a series of total internal reflections.
What are the similarities and differences between electron and positron? +
They have the same mass but opposite charge.
What does the binding energy per nucleon tell us about a certain nuclide? +
The stability of the nucleus
Simple harmonic motion is isochronous, what does that mean? +
That means the time period of a SHM does not depend on the amplitude.
What property of sound wave can help us to determine the position of cracking inside an object. + How does a standing wave form between two boundaries? +
Two identical waves traveling in opposite directions undergo interference.
Which phenomenon is related to the measurement of the speed of vehicles using radar? + What is an equipotential line? +
This is the line with the same electrical potential.
How does an electric field line relate to an equipotential line? +
They are perpendicular to each other.
Why is the electron beam used to probe a structure of matter? +
Because the electron beam shows wave nature.
