Physics Flashcards
SI unit of amount of substance.
Mole
SI unit of luminous intensity
Candela
A cylinder with platinum-iridium alloy is used to define the kilogram. What is the name of this cylinder?
a. Le Grand K
b. pti alloy
c. standard kilogram
d. standard mass
a. Le Grand K
What is the cgs unit of force?
a. Newton
b. erg
c. dyne
d. poise
c. dyne
Only used when recording any measurements.
Uncertain digits
Only use when you are multiplying or dividing measured numbers
Significant Figures
These are always significant
- Nonzero numbers
- Sandwiched zeros
- Zeros that fall both at the end of the number and after the decimal point
These will never be significant number
zeros that act as placeholders
It is usually stated that every particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
Law of Universal gravitation
The “triple point” of a substance is that point for which the temperature and pressure are such that:
solid, liquid, and vapor are all in equilibrium
the lowest velocity which a body must have in order to escape the gravitational attraction of a particular planet or other object.
Escape Velocity
thermal energy whose transfer to or from a substance results in a change of temperature
Sensible heat
the heat required to convert a solid into a liquid or vapor, or a liquid into a vapor, without change of temperature.
Latent heat
The amount of heat required to change 1 g of a substance at the temperature of its melting point from the solid to the liquid state without changing temperature.
Latent heat of fusion
It is defined as the heat required to change one mole of liquid at its boiling point under standard atmospheric pressure.
Latent heat of vaporization
Which one of the following statements is true?
a. Temperatures differing by 25◦ on the Fahrenheit scale must differ by 45◦ on the Celsius scale
b. 40K corresponds to −40◦ C
c. Temperatures which differ by 10◦ on the Celsius scale must differ by 18◦ on the Fahrenheit scale
d. Water at 90◦ C is warmer than water at 202◦ F
c. Temperatures which differ by 10◦ on the Celsius scale must differ by 18◦ on the Fahrenheit scale
statement that the total radiant heat power emitted from a surface is proportional to the fourth power of its absolute temperature.
Stefan-Boltzmann Law
a law stating that the ratio of the sines of the angles of incidence and refraction of a wave are constant when it passes between two given media.
Snell’s law
The light ray can actually bend so much that it never goes beyond the boundary between the two media.
total internal reflection.
the scientific study of sight and the behavior of light, or the properties of transmission and deflection of other forms of radiation.
Optics
The type of lens used to cure farsightedness is ______________ lens. a. Concave b. Convex c. Biconcave d. Plano – convex
Convex
The laws of physics are the same for all observers in any inertial frame of reference relative to one another
Relativity
Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
Relative of Simultaneity
Moving clocks are measured to tick more slowly than an observer’s “stationary” clock.
Time dilation
Objects are measured to be shortened in the direction that they are moving with respect to the observer.
Length contraction
No physical object, message or field line can travel faster than the speed of light in a vacuum.
Maximum speed is finite
energy and mass are equivalent and transmutable.
Mass-energy equivalence
Clocks run slower in deeper gravitational wells.
Gravitational Time Dilation
Orbits precess in a way unexpected in Newton’s theory of gravity. (This has been observed in the orbit of Mercury and in binary pulsars).
Precession
Rays of light bend in the presence of a gravitational field
Light defraction
Rotating masses “drag along” the spacetime around them.
Frame Dragging
the universe is expanding, and the far parts of it are moving away from us faster than the speed of light.
Metric Expansion of space
it deals with the study of light and particles at atomic and smaller level
Quantum mechanics
states that the current through a conductor between two points is directly proportional to the voltage across the two points.
Ohm’s Law
Nuclear sizes are expressed in a unit
named
a. Fermi c. Newton
b. Angstrom d. Tesla
Fermi
Lightyear is a unit of
a. time c. light
b. distance d. intensity of light
b. distance
Mirage is due to
a. unequal heating of different parts of
atmosphere
b. magnetic disturbances in the atmosphere
c. depletion of ozone layer in the
atmosphere
d. equal heating of different parts of the
atmosphere
a. unequal heating of different parts of
atmosphere
Stars appears to move from east to
west because
a. all stars move from east to west
b. the earth rotates from west to east
c. the earth rotates from east to west
d. the background of the stars moves from
west to east
b. the earth rotates from west to east
If two bodies of different masses,
initially at rest, are acted upon by the same
force for the same time, then both bodies
acquire the same
a. velocity c. acceleration
b. momentum d. kinetic energy
b. momentum
Out of the following, which is not
emitted by radioactive substances?
a. electrons
b. electromagnetic radiations
c. alpha particles
d. neutrons
d. neutrons
Sound waves in air are
a. transverse c. electromagnetic
b. longitudinal d. polarized
b. longitudinal
Materials for a rain-proof coats and
tents owe their water-proof properties to
a. surface tension c. specific gravity
b. viscosity d. elasticity
a. surface tension
It takes much longer to cook food in the
hills than in the plains, because
a. in the hills the atmospheric pressure is
lower than that in the plains and therefore
water boils at a temperature lower than 100
deg C causing an increase in cooking time
b. due to a lower pressure on the hills, the
water boils at a temperature higher than
100 deg C and therefore water takes longer
to boil
c. in the hills the atmospheric density is low
and therefore a lot of heat is lost to the
atmosphere
d. in the hills the humidity is high and
therefore a lot of heat is absorbed by the
atmosphere leaving very little heat for
cooking
a. in the hills the atmospheric pressure is
lower than that in the plains and therefore
water boils at a temperature lower than 100
deg C causing an increase in cooking time
Intensity of sound at a point is
_____________ its distance from the source
a. directly proportional to
b. inversely proportional to
c. directly proportional to square of
d. inversely proportional to square of
d. inversely proportional to square of
Of the four locations mentioned below
the highest inside temperature will be
attained in the pressure cooker operated
with the pressure valve open.
a. at sea level
b. at the top of Mt. Everest
c. at a place below sea level
d. in an aeroplane flying at a height of 10km
with inside pressure maintained at the sea
level
c. at a place below sea level
Mercury is commonly used as a
thermodynamic fluid rather than water
because
a. specific heat of mercury is less than water
b. specific heat of mercury is more than
water
c. mercury has greater visibility than water
d. density of mercury is more than the water
c. mercury has greater visibility than water
